Security Engineer - Detection & Response

About the Team You Will JoinThe Security Division of Toss Bank consists of various teams including Security Policy, Privacy Protection, System Security, Network Security, Security Red Team, Security Blue Team, IT Service, and Security Audit teams.The Network Security Engineer at Toss Bank will be responsible for the implementation and management of internal and external firewall systems, along with various tasks related to network security, including the operation of DDoS, IPS, and WAF systems.The Security Division collaborates with multiple teams to create a safe and reliable service for Toss Bank. The Network Security Team particularly works closely with product groups, and Legal & Compliance, Platform Engineering, and Internal Audit teams to ensure compliance and internal controls.Toss Bank's Security Division is committed to securing electronic financial transactions for clients and providing a safe working environment for employees.Responsibilities You Will HaveManage and improve network security solutions (FW, DDoS, IDS/IPS, WAF, Suricata) to protect services and employee work environments.Monitor and respond to network attacks and anomalies in real-time, continuously reviewing, tuning, and optimizing detection policies and rules.Design stable network security architecture and lead the construction and enhancement of new systems.Enhance operational efficiency through automation, creating an environment where security personnel can focus on strategic tasks.Ideal Candidate ProfileExperience in building and operating network security solutions (FW, DDoS, IDS/IPS, WAF, Suricata).Ability to analyze network security events/logs and experience in understanding and responding to various attacks.A deeper understanding of enterprise security infrastructure beyond simple equipment operations, focusing on policy, permissions, assets, and risk-based operations.Experience or fundamental understanding of network security architecture design, as well as experience in network troubleshooting and packet analysis (e.g., using Wireshark).Please Include the Following in Your ResumeRather than listing projects, we recommend detailing your roles, contributions, and results with specific examples.If you have experience designing network security architecture, detecting/blocking intrusions through pattern/signature analysis, or participating in drills, please mention them.Especially if you have detailed experiences in building/operating network security solutions or troubleshooting, please describe them thoroughly.

About the Team You'll JoinThe Network Security Engineer at Toss Securities is part of the Network Engineering Team, collaborating closely with Network Engineers and IDC Managers.We work with top talents across various sectors, including finance, commerce, portals, and gaming, to establish and support secure networks for both external and internal customers.Our goal is to ensure that our teams can focus on product development by building robust infrastructure capable of supporting the largest retail securities firm in the market, driving automation for faster product launches. Your ResponsibilitiesAs a Network Security Engineer, you will manage security devices such as firewalls and VPNs to protect our customers and teams.Maintain a reliable, high-availability network that operates 24/7, continuously improving its resilience.Collaborate on the design and implementation of networks that interact with applications and servers.Build and operate network security devices, providing security foundation technologies within the data center. Who We Are Looking ForA minimum of 5 years of experience in building and operating network security devices.Experience in analyzing, optimizing, and maintaining firewall policies is essential.Strong understanding of TCP/IP protocols with packet analysis experience for troubleshooting.Experience with API integration of network security devices or scripting for automation is a plus.Familiarity with financial information protection regulations and experience in related implementations is advantageous.Experience designing and building security network architectures optimized for high traffic is highly desirable.Experience in public cloud environments (AWS, GCP, Azure) is a strong plus. Resume RecommendationsPlease describe a memorable technical issue you resolved (optimization, bug fix, etc.).Detail your contributions to projects, including your role, technologies used, and outcomes before and after the project. Journey to Joining Toss SecuritiesApplication submission > Technical interview > Cultural fit interview > Reference check > Salary negotiation > Final acceptance and onboarding. Please NoteAny inaccuracies in your resume or disciplinary history during employment may result in cancellation of the hiring process.Candidates identified as ineligible according to Toss Securities' regulations may have their applications canceled.Persons with disabilities and veterans will be given preference in accordance with applicable laws.

About the Team You'll Join The Network Security Engineer at Toss Securities is part of the Network Engineering Team, collaborating closely with Network Engineers and IDC Managers. You will work alongside top talents from diverse sectors including finance, commerce, portals, and gaming, focusing on building and supporting secure networks for both external and internal clients. Our goal is to provide robust support for product development, enabling rapid deployment by enhancing our infrastructure to handle large-scale traffic and pushing for automation. Your Responsibilities Upon Joining As a Network Security Engineer, you will be responsible for security devices in the network area, including firewalls, DDoS protection, and VPNs to safeguard Toss Securities' clients and teams. You will perform regular preventive maintenance to ensure the stable operation of security equipment. Management and improvement of Toss Securities' security device monitoring solutions will be part of your role. You will build and operate network security devices, providing security-based technology within the data center. Ideal Candidate Profile A degree in Information Security, Computer Engineering, Information Communication, or a related field is required. A solid understanding of networks and security devices is essential. High proficiency in TCP/IP protocols and experience in packet analysis for troubleshooting are preferred. Experience with security system API integration or work automation is a plus. Prior experience in security training or practical security work is advantageous. Resume Recommendations Please describe a memorable technical issue you resolved (optimization, bug fixes, etc.). Detail projects you contributed to, focusing on your role, technology stack used, and improvements made. The Journey to Joining Toss Securities Application submission > Job interview > Cultural fit interview > Reference check > Salary negotiation > Final acceptance and onboarding. Important Notes False information in your resume or disciplinary issues in your work history may result in cancellation of your application. Applicants who fall under hiring restrictions per Toss Securities policies may also have their applications canceled. Individuals with disabilities or veterans are prioritized according to relevant laws. A Message for Future Colleagues The Network Security Engineer at Toss Securities creates and manages a secure and robust network structure both on-premises and in the cloud. This role goes beyond equipment management; it involves understanding service flows and traffic to continuously innovate better structures. The position requires proactive identification of potential threats and developing solutions. Our team takes initiative to investigate issues, identify root causes, and suggest efficient solutions swiftly, respecting each other's opinions while collaboratively ensuring the stability of financial services. We strive to continuously create improved methods rather than sticking to established practices.

Join Our Team! The Network Engineering team is tasked with establishing Toss Securities' network and security systems, along with managing data center operations. We collaborate with exceptional team members from diverse sectors including finance, commerce, portals, and gaming. Our goal is to support product focus by ensuring infrastructure capable of handling large-scale traffic and driving automation for quicker product releases. Your Responsibilities: Install and maintain Toss Securities' network and security devices, conducting regular status checks and resolving operational issues. Register and manage asset information for network and security devices (serial numbers, status, locations, etc.). Document work logs and change history for installation, migration, and decommissioning tasks. Oversee and enhance Toss Securities' network monitoring solutions. Provide rapid onsite response and first-level troubleshooting during incidents. Plan and support schedules for regular inspections of network and security devices. Be available for night or weekend maintenance when necessary. Manage cable connections for servers and storage, supervising cable installation by contractors. Who We Are Looking For: At least 5 years of experience in network technical support and field engineering. Understanding of network cabling standards and wiring practices is essential. Ability to respond effectively to incidents and perform basic network troubleshooting. Experience in collaborating with maintenance vendors and managing inspection documentation. Operational experience with major network equipment like Cisco and Arista is required; experience with Citrix NetScaler is a plus. Familiarity with security devices such as firewalls and VPNs, alongside a strong understanding of network security is preferred. Application Recommendations: In your resume, highlight a memorable case of technical problem-solving (optimization, bug fixing, etc.). Detail projects you've contributed to, including duration, roles, technology stack used, and improvements made. Your Journey with Toss Securities: Application submission > Job interview > Cultural fit interview > Final acceptance and onboarding. Please Note: This position is a contract role with a duration of one year. Any discrepancies in the resume or disciplinary records may result in cancellation of employment. Applicants subject to hiring restrictions or disqualifications as per Toss Securities' policies may have their applications canceled. Applicants with disabilities or veterans will receive preferential treatment in accordance with relevant laws. A Note for Future Colleagues: “At Toss Securities, you can experience both the constraints of a financial infrastructure and the trendy mobile services of an IT company!” The financial infrastructure in South Korea can be quite restrictive, limiting the breadth of experiences. However, at Toss Securities, you have the responsibility and authority to implement solutions that benefit the business, allowing for valuable experiences without being bound by irrelevant solutions dictated from above.

Welcome to the Journey of Joining daangn Team!At daangn, we strive to create an environment where individuals can grow alongside the company's expansion. We are dedicated to facilitating moments of joy and collaboration with wonderful colleagues. Introducing the Network TeamThe Network Team aims to deliver secure and high-speed network services to daangn customers. We design and operate a network environment optimized for hyperlocal businesses and a global service network, ensuring that daangn users remain seamlessly connected while being responsible for infrastructure stability and scalability.We enhance efficiency by automating repetitive operational tasks and visualize traffic flow and status across the network in real-time to quickly detect issues and respond proactively. Our core role also involves maintaining service quality during traffic surges and protecting the platform from network security threats.Key ResponsibilitiesDesign and operate daangn's Service/Office Network Architecture (Cloud, Wired, Wireless).Design and operate Network Security Architecture.Develop and operate Network Observability and Automation platforms.Ideal CandidateMinimum of 5 years of practical experience in Network Engineering.Understanding and operational experience with routing protocols such as OSPF and BGP.Experience with AWS or GCP cloud network environments (VPC, TGW, NAT Gateway, Cloud WAN, Direct Connect, Cloud Router, Interconnect).Experience operating wired and wireless network devices (Router, Switch, Wireless Controller, Access Point).Experience with NGFW, IPSEC VPN, and SSL VPN (ZTNA) (AWS Network Firewall, Palo Alto, Fortinet).Experience in building network monitoring systems.Ability to troubleshoot through network packet analysis.No restrictions on overseas travel.Preferred QualificationsExperience in network operations within IT companies or large-scale cloud service environments.Deep understanding of Kubernetes environments.Strong knowledge of Zero Trust frameworks.Experience analyzing network packets to block pattern and signature-based security threats.Interest in developing or automating network monitoring platforms (Go, Python, etc.).Proficient with IaC tools such as Terraform or Ansible.Additional InformationFull-time roles include a 3-month probation period.We prioritize candidates with disabilities and veterans in accordance with the 'Act on the Promotion of Employment of Disabled Persons' and 'Act on the Honorable Treatment and Support of Veterans'.Successful video interview candidates will be given assignments, which will be discussed in the role interview.Application Process1. Document screening → 2. Video interview → 3. Role interview (assignment) → 4. Culture fit interview and reference check → 5. Offer.

Join Our Dynamic Team! As a Network Engineer at Toss Securities, you will be a crucial member of our Network Engineering Team, collaborating closely with Network Security Engineers and IDC Managers. Your role will involve building systems for both external and internal clients while managing our IDC. Work alongside exceptional team members from various sectors, including finance, commerce, portals, and gaming. We are committed to our mission of enabling our teams to focus solely on product development by building robust infrastructure capable of supporting large-scale traffic and promoting automation for faster product launches. Your Responsibilities: Maintain and enhance all network systems at Toss Securities to ensure optimal performance. Design and operate the office network environment for Toss Securities. Architect and implement multi-data center networks to ensure uninterrupted service. Your Qualifications: Minimum of 7 years of experience in network design and operations, specifically with dynamic routing protocols (BGP, OSPF) for multi-data center integration. Strong understanding of various network protocols across L1 to L7 (IP, MAC, TCP, HTTP, SSL, mTLS) and experience in packet analysis. In-depth knowledge and experience of NETWORK OVERLAY technologies (ACI, VXLAN, EVPN, MP-BGP, IS-IS, Fabric). Experience in operating L7 switches with BGP-based Route Health Injection (RHI) for server load balancing. Preferred Qualifications: Experience collaborating with various internet service providers (ISPs) and cloud service providers for multi-data center integration and line load balancing. Background in designing and implementing networking and security devices for large data centers. Familiarity with open-source network monitoring solutions or relevant development experience. Experience in AI data center networking and ANYCAST network services. Experience in automating L2 & L3 switches and L4 & L7 load balancers using APIs. Experience conducting BMT and PoC and writing RFPs. Experience building and optimizing cloud networks, especially in hybrid and multi-cloud environments. Experience using AI-driven MCP for infrastructure operations. Resume Guidelines: Describe your most significant technical problem-solving experiences (optimizations, bug fixes). Detail projects you have contributed to, including duration, role, technology stack, and improvements made. Share experiences of attempts and failures aimed at enhancing network operations. Specify the vendors of the equipment you have worked with. Application Process at Toss Securities: Application Submission > Job Interview > Cultural Fit Interview > Reference Check > Compensation Negotiation > Final Offer and Joining. Please Note: Any discrepancies or disciplinary issues in your resume or work history may result in the cancellation of your application.

Team and Collaboration The Security team at Toss brings together a range of professionals: CISO, Security Engineers, Security Researchers, Information Security Managers, Privacy Managers, and IT Managers. This group works closely with the Infra team, product development silos, Legal, and Compliance to build secure services for Toss. Members also connect with security peers across subsidiaries, sharing knowledge and collaborating on specialized areas. Working here means helping to build and improve security systems that support Toss in delivering reliable services. What You Will Do Design and operate AWS cloud security architecture, managing cloud security infrastructure such as CSPM and CWPP. Set up detection and response systems using logs, and automate security policies with IaC tools like Terraform. Manage IDS/IPS, WAF, and DDoS protection systems, addressing network vulnerabilities proactively. Design and refine detection policies through traffic and packet analysis, including regular expressions. Collect and respond to security events using SIEM/SOAR, and operate endpoint solutions like EDR and DLP to strengthen organizational security. Lead security design at the service architecture level and support technical compliance requirements. Requirements At least 5 years of experience as an in-house Security Engineer. Hands-on experience building and operating security systems in AWS cloud environments. Background in constructing and managing network security solutions (IDS/IPS, WAF) and capability in traffic and packet analysis, including optimizing detection policies. Experience with SIEM for event correlation analysis and developing threat hunting and response playbooks is preferred. Familiarity with endpoint security solutions such as EDR, AV, and DLP, as well as handling malware responses and configurations, is a plus. Technical experience with security certifications and financial regulations (ISO27001, PCI-DSS, ISMS-P) is advantageous. Resume Tips Describe previous roles with clear examples, emphasizing project contributions, technology stacks, and measurable improvements. Share how you approached and solved challenges, including your thought process. Include experiences where you identified and responded to security threats or resolved technical and managerial issues. Highlight specific cases where you learned and applied new security technologies or addressed emerging threats. Hiring Process Application Job Interview Cultural Fit Interview Reference Check Compensation Negotiation Final Offer and Onboarding Voices from the Team "I enjoy working with exceptional colleagues." One team member who joined after serving as the sole security officer at a previous company shared how building Toss's security infrastructure alongside the team has brought stability and a stronger security posture. This collaborative environment has become a source of pride as the team secures valuable assets together. Toss encourages setting personal goals every half-year, empowering team members to take ownership and collaborate with accomplished peers.

About the Team You Will JoinThe Security Infrastructure team is dedicated to designing security architectures that ensure the safe expansion of Toss's business, implementing and automating these architectures in real-world environments.This team covers cloud, network, and endpoint security, directly designing and implementing security policies and controls based on key infrastructure.We select technology stacks, create log architectures, and access control models, building a structure that defends against actual threats rather than merely implementing security for security's sake.Our team consists of members with diverse experiences, primarily from corporate information security roles and specialized information protection companies.We are looking for individuals who start with the question of “Why?” to improve security structures and design safer, more efficient methods while balancing technology and business needs.Responsibilities You Will UndertakeDevelop and manage information security solutions that protect Toss's services and employee environments.Establish and operate an access control system for internal information systems.Build a network separation environment and information leak response systems in accordance with financial compliance.Plan and operate systems to enhance security visibility and access control systems.Conduct modern threat analysis and incorporate global trends while establishing AI-based detection and analysis systems and real-time response strategies.Additional ResponsibilitiesDesign, build, and operate infrastructure security architectures across cloud (AWS/GCP/Azure) and on-premises/hybrid environments, covering networks, servers, databases, and containers. You may focus on either cloud or network based on your strengths.Design and reliably implement core security policies like IAM, network segmentation, access control, and encryption (KMS) in real environments.Structure repetitive security operations based on IaC and automation while collaborating with other teams to establish actionable security standards.Analyze security events and breach incidents to design and fundamentally improve security structure, policies, and automation.Ideal CandidateWe are searching for individuals with over 3 years of relevant experience.You should have experience dealing with infrastructure across cloud, network, and systems, not limited to one area.Experience in enhancing detection and response systems using security solutions like CSPM/CNAPP, SIEM, EDR, WAF, and KMS is essential.Experience in designing or improving operational efficiency through security automation and IaC with tools like Terraform/CloudFormation, Ansible, and Python is required.You should have experience interpreting and integrating security requirements in financial and regulatory environments (ISMS-P, ISO27001, PCI-DSS).

About the Network Engineer Internship at Daangn Daangn is looking for a Network Engineer Intern to join the Infrastructure (Network) team in Seoul. This is a 3-month internship designed for those eager to develop technical skills while supporting a platform that connects hyperlocal businesses and users worldwide. Meet the Network Team The Network Team builds and maintains secure, high-performance network services for Daangn customers. The group designs and operates a network environment tailored for both local and global needs. Team members automate routine tasks, monitor traffic flow and network status in real time, and respond quickly to issues. Maintaining service quality during traffic spikes and protecting the platform from security threats are central to the team’s mission. What You Will Do Help design and operate Daangn’s service and office network architecture (cloud, wired, wireless) Assist in designing and operating network security architecture Contribute to the development and operation of network observability and automation platforms Who We’re Looking For Currently pursuing or recently completed a degree in Computer Science, Information Communication, Information Security, or a related field Solid understanding of basic networking concepts, including the OSI model and TCP/IP Knowledge of IPv4 addressing and subnetting Basic experience with physical network devices such as switches and routers Familiarity with network security concepts, including firewalls Ability to use scripting languages like Python or Bash at a basic level or higher Motivated to learn and grow proactively Preferred Qualifications Hands-on experience with AWS or GCP consoles Understanding of REST API calls and integrations Practical experience with networks or infrastructure through personal projects or coursework Knowledge of security principles such as encryption, authentication, and access control Interest in network observability or automation Attention to documentation and willingness to share knowledge within the team Additional Details This internship lasts for 3 months. Daangn gives preference to candidates with disabilities or veterans, in line with the 'Promotion of Employment for the Disabled and Vocational Rehabilitation Act' and the 'Act on the Honorable Treatment and Support of Persons of Distinguished Service.' Applications close on May 3rd, 11:59 PM. The deadline may change depending on circumstances. The expected start date is June 1st, though this may be adjusted if needed.

About the Team You'll Join The Security Division at Toss Securities is composed of the Security Policy Team, Security Engineering Team, Security Audit Team, and IT Innovation Team, with the Security Engineering Team focusing on technical security tasks. The security team receives comprehensive support across the organization to ensure the safety of Toss Securities services and collaborates closely with all departments. Each team member actively engages with peers in similar roles across subsidiaries, sharing knowledge and experiences to achieve common goals. The team comprises members with diverse experience levels ranging from 1 to 20 years, many of whom have backgrounds in information security firms and corporate information security roles. This year, the Security Engineering Team aims to enhance its information security management system to achieve international recognition and strengthen its capabilities in SOAR, ZTNA, and Cloud/Container security. Your Responsibilities You will identify potential security threats, data leakage risks, and compliance violations across endpoint environments and work to mitigate these issues. Analyze conflicts between security requirements and actual workflows, implementing solutions that balance security and user experience. Address endpoint security issues by analyzing root causes and implementing improvements to prevent recurrence. Manage to maintain consistent endpoint security standards throughout the device lifecycle. Design and automate policy-based control logic to evaluate endpoint status, user context, device posture, and the policy settings of security solutions to determine access permissions. Integrate endpoint security controls with IAM and access control to enhance the overall security framework. Who We're Looking For Experience in designing and customizing detection rules, blocking policies, and monitoring logic based on potential security threats in endpoint environments. Experience in designing and implementing technical solutions such as policy exceptions, temporary authorizations, and selective monitoring to ensure security controls do not hinder actual workflows. Experience in investigating endpoint security issues through log analysis, process tracing, and filesystem investigation at the Windows and macOS levels to identify root causes and establish preventive measures. Experience in designing and managing systems to maintain consistency in security standards throughout the entire lifecycle of devices, from provisioning to disposal. Ability to implement a Policy Decision Point that determines access permissions based on endpoint status information collected via security solution APIs, with experience in Python/Go, OPA, or AI/MCP-based tools being a plus. Experience in integrating security context collected from endpoints (such as device compliance and threat detection results) with IAM, network, and application layer access controls via SCIM, Webhook, and API would be advantageous. Your Pathway to Joining Toss Securities Application Submission > Job Interview > Cultural Fit Interview > Reference Check > Negotiation of Terms > Final Acceptance and Onboarding Additional Information Employment may be rescinded if false information is found in the resume or if any disciplinary actions are confirmed during employment history. Individuals who are prohibited from employment under Toss Securities regulations or have disqualifying factors may have their applications canceled. Individuals with disabilities and veterans will receive preferential treatment in accordance with relevant laws. A Note for Potential Colleagues We value innovation, collaboration, and a passion for security in our team. Join us to make a significant impact in the world of cybersecurity!

The Network Engineer role at Toss is part of the Infra Engineering Tribe in Seoul. This team collaborates with System Engineers and InfraOps Engineers to deliver infrastructure that keeps Toss services reliable, fast, and secure. The work supports Toss’s mission to advance financial technology and innovation. Role overview Build and manage network infrastructure for a range of Toss services. Develop and operate monitoring systems to ensure smooth network operations. Optimize network performance, addressing issues to maintain high service quality. Requirements Less than 5 years of experience in network construction. Strong understanding and hands-on experience with L2/L3 data center networks. Demonstrated initiative to improve networks and expand technical skills. Familiarity with TCP/IP and troubleshooting based on it is preferred. Experience working with others to identify and resolve network issues is valued. Experience with IPSEC VPN and L4 (SLB) is a plus. Knowledge of traffic or log monitoring using open source tools is advantageous. Resume tips Describe two memorable cases where technical issues were resolved, such as optimizations or bug fixes. Highlight project contributions, specifying your role, the technology stack, and improvements made before and after your involvement. Hiring process Application submission Job interview Cultural fit interview Reference check Salary negotiation Final acceptance and onboarding

About the Team You Will Join The Security Division at Toss Bank comprises multiple teams including Security Policy, Privacy Protection, System Security, Network Security, Security Red Team, Security Blue Team, IT Service, and Security Audit. The Security Engineer (Endpoint Security) will work within the Security Division to manage various tasks aimed at protecting endpoints from external threats, particularly as part of the System Security Team. The Security Division collaborates with various teams to create secure and reliable services, and the System Security Team works closely with product organizations, Legal & Compliance, Platform Engineering, and Internal Audit to ensure security and regulatory compliance. We are dedicated to providing a secure environment for electronic financial transactions and to seamlessly integrating security into the daily operations of our users. Key Responsibilities Operate security solutions to protect Toss Bank's customers. Build, manage, and operate endpoint security solutions including Antivirus (AV), Data Loss Prevention (DLP), Network Access Control (NAC), and Endpoint Privilege Management (EPM). Ensure stable operation of endpoint security solutions and quickly resolve operational issues. Establish endpoint security policies for Windows and Mac OS and engage in proactive information security activities. Analyze events through endpoint security solutions and conduct threat response activities. Desired Qualifications A minimum of 5 years of experience in operating endpoint security solutions. Deep understanding of PC and server operating systems. Familiarity with basic networking and architecture concepts. Strong understanding of the operational principles and policies of endpoint security solutions. Experience with open-source endpoint security solutions and automation of security solutions is a plus. Application Instructions Please include detailed descriptions of your responsibilities and specific examples in your resume, as simple project lists may not be sufficient. We recommend submitting a portfolio along with your resume. Highlight your experiences and knowledge relevant to the job area in your application. In your portfolio, please document your studies or practical experiences in security technology and your level of understanding. Join Us at Toss Bank Application Submission > Job Interview > Cultural Fit Interview > Reference Check > Compensation Discussion > Final Acceptance and Onboarding Please Note Any discovery of false information in your resume or disciplinary actions during your employment history may result in cancellation of your application.

Welcome to the Daangn Team!At Daangn, we strive to create an environment where individuals can grow alongside the company's success.We are here to assist you in reaching that moment of joy while working with wonderful colleagues. Introducing the Security TeamThe Security Team aims to ensure that Daangn provides services securely. We defend against external attacks and prevent the leakage of valuable internal information. All our activities comply with various information protection laws and regulations. By understanding Daangn's business model, we provide clear standards that are implemented technically. Through these efforts, we create a reliable service that users can trust.Key ResponsibilitiesAssess and improve security risks in AI/ML-based service environments.Audit and manage access controls and security configurations for AI service components, including training data, model files, APIs, and infrastructure.Monitor and respond to security issues in LLM and generative AI environments, such as prompt injection and data leaks.Analyze AI service logs to detect anomalies, investigate security events, and resolve issues.Conduct security vulnerability assessments and actions during model deployment and operation.Establish and continuously improve security guidelines and policies.We Seek Candidates Who:Have experience in vulnerability assessments, penetration testing, or incident response.Are familiar with LLMs and understand the operational mechanisms of prompt-based services.Have a foundational understanding of cloud architecture (IAM, networking, storage) in platforms like AWS, GCP, or Azure.Possess basic knowledge of AI/ML or LLM service structures.Have experience in log analysis and root cause identification.Are proactive in addressing security issues, focusing on improvements rather than just reporting.Preferred Qualifications:Understanding of ML pipelines (data collection → training → deployment → monitoring).Experience with container environments such as Docker and Kubernetes.Have at least one year of experience in security, cloud, backend, or ML engineering.Have experience in improving repetitive tasks through security automation or scripting.Regularly learn about and share new AI security issues or trends.Additional InformationThere is a 3-month probation period for full-time hires.As per the Employment Promotion and Vocational Rehabilitation of Persons with Disabilities Act and the Act on the Honorable Treatment and Support of Veterans, individuals with disabilities and veterans will receive preferential hiring.

#LI-DNI Join Our Dynamic Security Team! As a Security Engineer at Tosscareers, you will be part of the Information & Security Tribe, handling technical operations within the Security Purple Team and Security Green Team. The Security Purple Team is a hybrid of Red and Blue teams, focusing on event analysis, incident response, vulnerability assessments, penetration testing, and scenario-based threat modeling. We prioritize customer safety and collaborate closely with all teams to enhance Toss's security measures. Your Responsibilities Will Include: Designing, building, and operating SIEM (Splunk, Opensearch, Elasticsearch). Creating robust architectures for secure log collection across various environments (On-Prem, AWS, K8S). Ensuring stable operation and enhancement of log pipelines (NIFI, KAFKA, Hadoop). Establishing and managing logging/monitoring systems for performance optimization and incident response of the Security Data Platform (SIEM). Designing and normalizing standard models for various logs to improve log analysis efficiency. We Are Looking For Candidates Who: Have experience in designing and building scalable and optimized SIEM systems. Can identify and resolve issues in log collection, data loading, search, and query building processes. Have worked with heterogeneous security log pipelines in On-Prem and AWS environments (ETL, ELT). Have standardized various forms of security logs (OCSF, CIM, etc.) for easier analysis. Have automated tasks using Python scripting. Resume Tips: Detail specific examples of your work, particularly your roles in projects, the technologies used, and improvements made before and after. Explain any challenges faced during problem-solving and how you addressed them. If you have diverse problem-solving experiences (technical, managerial), provide concrete examples. Include specific cases where you applied learned technical skills to your work.

Security Engineers at daangn focus on protecting infrastructure and keeping user data safe. This position centers on finding vulnerabilities through penetration testing and setting up strong security protocols across our systems. Role overview This role involves hands-on work with infrastructure security in Seoul. The main responsibility is to identify and assess security risks, then act to address those issues. Attention to detail and a methodical approach are important, as your work directly impacts the safety of our platform. What you will do Conduct penetration tests to uncover vulnerabilities in our infrastructure Implement and maintain security protocols to meet high standards Support ongoing efforts to protect user data and system integrity Requirements Experience with infrastructure security and penetration testing Ability to identify, analyze, and address security vulnerabilities Commitment to maintaining strong security practices

Join Our Team!The Internal Infrastructure Engineer at Toss CX is a vital member of the General Affairs Team, responsible for establishing and implementing optimal internal infrastructure strategies that align with the rapid expansion of our business.This role transcends basic IT support, as you will enhance our network and security systems based on financial security guidelines, ensuring a safe and engaging work environment for all team members.Your Responsibilities:Design and Stabilize Internal IT Infrastructure: Create a scalable internal network and server infrastructure that matches Toss CX's business direction and organizational size, ensuring reliable operations.Manage Office Network and Security Infrastructure: Optimize and maintain the overall office network architecture, including L2/L3 switches and access points. Implement and manage cutting-edge security solutions like Zscaler, NAC, and WIPS to uphold a zero-trust work environment.Enhance IT Governance and Environment: Lead IT projects to establish an account management system based on Okta and Active Directory, standardizing internal infrastructure and maximizing work efficiency.

Key ResponsibilitiesCraft and implement a robust end-to-end security architecture tailored for SoC-based products.Develop features for Secure Boot and Anti-rollback mechanisms.Manage Key Provisioning alongside Hardware Root of Trust.Oversee Secure Lifecycle State management (LCS) for firmware, keys, and devices.Design and integrate security modules to enhance firmware and system-level defenses.Conduct thorough vulnerability assessments, attack surface evaluations, and implement memory protection hardening strategies.Integrate, validate, and optimize hardware cryptographic engines including AES/GCM engines, TRNG, PKA, RSA, PQC, and hash accelerators.Establish secure firmware update and rollback protocols along with comprehensive product lifecycle controls.QualificationsDeep understanding of embedded security principles, including Secure Boot, key management, and cryptography.Demonstrated experience with TLS, X.509, ECC, AES, and various cryptographic or security libraries.Proficient in C/C++ or Rust for developing secure system software.Experience identifying and analyzing security vulnerabilities in SoC/FPGA-based systems.Practical experience with hardware cryptographic engines and security IP blocks (e.g., AES/GCM, SHA accelerators, TRNG/DRBG, PKA).Solid understanding of firmware and key lifecycle management.Preferred QualificationsFamiliarity with TPM, HSM, TrustZone, OP-TEE, or related hardware security architectures.Experience in implementing secure firmware signing, provisioning, and deployment pipelines.Background in validating cryptographic engines under standards such as FIPS 140-3, NIST CMVP.Security engineering experience specifically for AI accelerators, networking chips, or SoCs.Contribute to development practices aligned with standards such as FIPS, PSA Certified, CAVP, and CMVP.

Toss Securities is seeking an IDC Infrastructure Engineer (Network & System) to help build and maintain the backbone of our data center operations in Seoul. This position focuses on ensuring the stability, efficiency, and continuous improvement of our large-scale infrastructure, covering everything from network design to physical equipment and operational processes. The role is primarily based at our modern data center (IDC), working closely with a team of network and system engineers. What you will do Design hardware architectures for network and server infrastructure, including equipment selection and implementation standards. Develop data center network architectures (such as Spine-Leaf and redundancy) and server/storage configurations. Define technical standards for bandwidth, NIC specifications (10G/25G/100G/400G), cabling (OM, LR/SR, MPO), and switch port setups. Plan physical infrastructure, taking into account rack space, power, and environmental needs. Set and manage organization-wide standards for equipment models, firmware, and configuration templates. Install, configure, and operate servers, storage, and network equipment on site, driving ongoing improvements. Oversee equipment transport, installation, and relocation, ensuring quality and safety throughout the process. Coordinate with contractors for cabling and equipment setup, maintaining technical standards and quality control. Monitor the IDC environment (power, temperature, network, equipment status) and respond proactively to anomalies. Lead first-level incident response and root cause analysis, working to prevent recurrence and resolve complex issues across network, system, and physical layers. Manage the lifecycle of IDC assets, ensuring data integrity and optimizing long-term operational plans for capacity, power, and space. Collaborate with colocation service providers and partners to manage schedules, quality, and costs. Automate repetitive operational tasks, such as firmware upgrades and configuration deployments, and build monitoring/CMDB integrations using SNMP and REST API. Establish and refine operational standards, procedures, and policies for ongoing efficiency. Requirements At least 5 years of experience in data center (IDC) or infrastructure design and operations. Experience designing data center network architectures (Spine-Leaf, redundancy, etc.). Understanding of server/storage hardware and operating systems (Linux, Windows, Hypervisor). Ability to design at the hardware level, with knowledge of NICs, cabling, and switch ASICs. Experience with IDC space planning, rack layout, power, and space design and operations. Background in large-scale equipment installation, relocation, and asset management within IDC operations. Problem-solving skills that address both physical and logical aspects of incidents. Strong communication skills for effective collaboration with contractors and internal teams. Experience with equipment implementation proof-of-concept (PoC), vendor evaluation, and performance validation. Proven ability to create infrastructure standard documents, such as design guides and operational procedures.

About the Team You'll JoinThe Security Division at Toss Securities consists of the Security Policy Team, Security Engineering Team, Security Audit Team, and IT Innovation Team, with the Security Engineering Team focusing on technical security tasks.The Security Division receives comprehensive support across the organization to create secure services and collaborates closely with all departments.The Security Division is made up of the Security Engineering Team and the Security Policy Team.Team members actively share experiences and knowledge with colleagues in similar roles within the company to achieve common goals.The team includes individuals with diverse experience levels, ranging from 1 to 20 years, most of whom have backgrounds in cybersecurity firms or as corporate security officers.In 2024, the Security Engineering Team aims to enhance its information security management framework to achieve international recognition, focusing on improving areas such as SOAR, ZTNA, and Cloud/Container security.Your ResponsibilitiesDevelop and manage Toss Securities' security monitoring system using SIEM.Gather and analyze various logs to create monitoring policies for security threats.Analyze and respond to security threats and incidents occurring in customer-facing services and employee work environments.Conduct incident analysis and response tasks.Ideal Candidate ProfileExperience in building and operating various log collection/analysis systems such as Splunk, ELK, and Kafka is essential.Proficient in creating correlation rules for sequential scenario detection in SIEM.Strong analytical skills for security incidents and security events are required.Ability to automate procedures for security log analysis, validation, and response development is necessary.Experience in threat response in various service environments, including IDC, CDN, Public Cloud, and Kubernetes, is a plus.Resume RecommendationsInclude at least two memorable examples of policies you created to detect security threats.If applicable, detail any cases of technical problem-solving (optimization, bug fixes, etc.) focusing on the technologies used and the outcomes achieved.Journey to Join Toss SecuritiesApplication Submission > Job Interview > Cultural Fit Interview > Reference Check > Salary Negotiation > Final Offer & OnboardingPlease NoteIf any false information is found in the resume or submitted documents, or if any disciplinary actions are confirmed during employment history, the hiring may be canceled.Hiring may be canceled for individuals who are prohibited from employment according to Toss Securities' regulations or who have disqualifying factors.Individuals with disabilities and veterans will be given preference according to relevant laws.A Word for Future Colleagues“You can enjoy working and growing as a security engineer in an environment where the latest technologies are actively adopted!”I am engaged in analyzing cybersecurity events and responding to incidents. To do this, additional data collection and expansion of the analysis system are necessary, and Toss's rapid collaboration culture allows me to focus quickly on the essence of analysis tasks.Working alongside experts in systems, networks, and security fields fosters my growth daily, and the active adoption of cutting-edge technologies makes it a pleasure for event analysts eager for trends to join us.