Security Engineer (Application Security)

• Trail of Bits seeks a Security Engineer II for our Application Security practice. You will conduct security assessments of client software, independently own substantial components or workstreams, identify and validate vulnerabilities across the application and system levels, and develop custom tooling alongside the team. You will own your analysis from discovery through client delivery and help clients understand and fix the issues you find
• This role bridges vulnerability research and applied security. Your work will be hands-on and autonomous: analyzing complex code, building custom tooling, conducting threat modeling and architecture reviews, and delivering findings that can withstand technical scrutiny
• It is distinct from roles centered on security operations, SOC work, GRC, compliance, policy, audit, or general security programs. Candidates from broader or adjacent security backgrounds should be prepared to talk through sustained, hands-on code-level security work they have personally completed
• At the Security Engineer II level, you should be able to take an ambiguous component, module, or attack surface, determine how to assess it, perform the analysis, and deliver clear findings with limited day-to-day direction. You will collaborate with a project lead and other security engineers while exercising independent technical judgment and improving the work of the team around you
• Security Assessment Ownership: Independently lead assessments of substantial components, modules, or systems within client engagements and own the work from scoping through delivery
• Vulnerability Discovery and Analysis: Find and validate vulnerabilities, establish root causes and exploitation paths, assess impact, and develop proof-of-concept code when appropriate
• Custom Security Tooling: Design and build targeted tools, harnesses, tests, or automation that expand assessment coverage and improve repeatability
• Architecture and Threat Modeling: Review complex software architectures, identify attack surfaces, data flows, trust and privilege boundaries, and recommend practical mitigations
• Client Communication: Produce clear, actionable findings, defend the evidence behind them, and lead technical discussions with client engineering teams
• Team Contribution: Review other engineers’ code and analysis, share techniques, and help improve the team’s technical approach
• Research and Innovation: Contribute new methods, open-source tools, and technical writing to Trail of Bits and the broader security community

Benefits

• Health Insurance with no-monthly-premiums
• Vision, Dental, Life & Disability Insurance
• Access to Kindbody for gynecology and fertility care
• Access to HealthAdvocate, Teledoc & OneMedical
• 401k with 5% company matching
• Ongoing bonus opportunities
• Competitive salaries
• ConnectYourCare Flex Spending Account (FSA)
• Commuter Benefits
• Fitness stipends
• Four weeks of PTO
• Fifteen company holidays
• 4 months paid parental leave
• Continuing education, public presentations and blog posts
• Recruiting & referrals
• End-of-year performance bonus
• Conferences & off-sites
• Company & team outings
• Virtual events
• Continuing education
• Training sessions & learning courses
• Internal research & development Projects
• Charitable donation matching
• Relocation assistance
• 1Password subscription
• Work from home stipend
• Remote work friendly

• Clear written and verbal communication, including experience presenting technical conclusions to software engineers or clients and contributing effectively on a distributed team
• Strong code-analysis skills across unfamiliar and complex codebases, including tracing execution and data flow, identifying logic and implementation flaws, and reviewing the security implications of system design
• Strong systems knowledge, including operating systems, IPC, privilege boundaries, system internals, and how applications interact with the platform around them
• Strong programming and debugging ability in at least two relevant languages, such as Rust, Go, C, C++, Python, JavaScript, TypeScript, or similar languages used in security analysis and tool development
• Working knowledge of memory-corruption vulnerabilities and mitigations, including the ability to reason about exploit primitives, defensive mechanisms, and the practical security impact of implementation choices
• Demonstrated ability to independently scope and execute a code-level security-assessment workstream, prioritize attack surfaces, build or adapt tooling, document evidence, and deliver findings
• Repeated vulnerability-discovery experience. You can talk through vulnerabilities you personally found or validated, including how you identified them, established exploitation paths and impact, and distinguished them from false positives or low-impact defects
• Typically 2+ years of directly relevant experience in application security, vulnerability research, security-focused software engineering, or a closely related area. Relevant experience may include professional work, research, open-source contributions, or substantial academic or independent projects; demonstrated depth and independence matter more than a strict year count
• Active or recent CTF participation, competition results, or comparable hands-on security challenges
• Published vulnerability research, CVEs, responsible disclosures, bug bounty findings, conference presentations, or technical writeups
• Contributions to open-source security tools, libraries, or research
• Experience with mobile application security, mobile system internals, or binary analysis on mobile platforms
• Experience assessing cloud platforms or infrastructure and working with tools such as Kubernetes, Helm, Terraform, or Ansible
• Experience with kernel code, drivers, reverse engineering, fuzzing, symbolic execution, or other low-level systems work
• Experience building security tools used by other engineers or across multiple assessments
• Experience leading client-facing technical discussions or mentoring other security engineers