Paranoids Corporate System Security Engineer II

Yahoo serves as a trusted guide for hundreds of millions of people globally, helping them achieve their goals online through our portfolio of iconic products. For advertisers, Yahoo Advertising offers omnichannel solutions and powerful data to engage with our brands and deliver results.

When you impact millions of people every day, you become a large target for adversaries of all types within all layers of the stack. Our job is to keep our users safe and make Yahoo one of the safest places on the Internet. We are the information security team at Yahoo; known as "The Paranoids".

As a Paranoids Corporate System Security Engineer, you help run the review function for everything employees use to get their work done - third-party SaaS, vendor integrations, employee-facing tools, AI/LLM products, and agentic connections entering the corporate environment. You will carry real reviews from day one, with senior reviewers backing you on the harder architecture calls.

• Perform hands-on security reviews of corporate systems - third-party SaaS, vendor integrations, employee-facing tools, and AI/LLM products - identifying risks, recommending controls, and escalating higher-risk architecture decisions to senior reviewers.
• Own the high-volume tiers of the review queue: intake triage, Okta onboarding, access and support requests, and baseline configuration checks, closing each to a documented disposition.
• Use AI-assisted tooling as a standard part of review work - triaging intake, digesting vendor documentation, and drafting first-pass dispositions - and verify the output before it goes on the record.
• Assist with MCP and agentic connection reviews - checking authentication and authorization, scope and consent, credential handling, and audit coverage against the established review rubric.
• Contribute to internal review tooling, rubrics, runbooks, and documentation, including the precedent library that makes future reviews faster.
• Support the annual corporate-product check-in program and help reconcile the SaaS inventory against review history to surface products that have fallen out of spec.
• Participate in ongoing learning, staying current with emerging threats across corporate SaaS, identity, and AI/agentic tooling.

• 3 years of experience in security review, IT or corporate security, or a related engineering or systems discipline with a focus on secure design or technical solutioning.
• Experience assessing third-party or SaaS products OR internal products - reviewing how a system authenticates, where its data flows, how it works, and what access it is granted.
• Understanding of security fundamentals - authentication, authorization, encryption in transit and at rest, logging, and secure communications.
• Working knowledge of SSO and of MFA enforcement in an identity provider such as Okta.
• Familiarity with AI/LLM application security basics such as sensitive data exposure through model inputs and outputs.
• Awareness of agentic and tool-use patterns (e.g., Model Context Protocol) and the questions they raise about scope, credentials, and audit.
• Hands‑on use of AI tools in day‑to‑day analysis work (summarizing documentation, drafting findings, triage), and the judgment to recognize where they get things wrong.
• Ability to work with product and business owners to explain a requirement, gather what is missing at intake, and validate that a control is actually in place.
• Strong written communication - able to document a review decision so the requester knows whether it blocks, who owns it, and what closes it.
• Ability to manage a queue: prioritize, keep tickets moving, and escalating before something ages out.

• Demonstrated capability of…