Tinypool: Prototype Pollution gadget in worker options leads to Remote Code Execution

[ Why it matters ]Priority signals

• Public proof-of-concept exploit exists (CISA SSVC)
• Critical severity: CVSS 9.5

[ Description ]Official description

Tinypool is a minimal Node.js worker thread pool implementation. Prior to 2.1.1, Tinypool constructs ThreadPool.options from a normal options object and reads the execArgv and env worker options in dist/index.js, allowing values inherited from a polluted Object.prototype to be copied into own properties and passed to worker_threads.Worker. An attacker who can first pollute either property can cause each newly spawned worker to load attacker-selected JavaScript through command-line preload arguments or NODE_OPTIONS, resulting in code execution with the host process's privileges and possible access to CI secrets, signing material, or build artifacts. This issue is fixed in version 2.1.1.

[ Fixes ]Fixes and patches

• tinypool 2.1.1Fixed version · GitHub Advisories · npm package tinypool: upgrade to 2.1.1 or later (affected <= 2.1.0)

[ Packages ]Affected open-source packages

• tinypool npmAffected <= 2.1.0 · fixed in 2.1.1 · GHSA-5gmw-xhrv-c9v3

[ References ]References

• github.com/tinylibs/tinypool/commit/24df4e730e7d0857a6d226c9b58f8924227404fd
• github.com/tinylibs/tinypool/pull/134
• github.com/tinylibs/tinypool/releases/tag/v2.1.1
• github.com/tinylibs/tinypool/security/advisories/GHSA-5gmw-xhrv-c9v3