[ CVE-2026-115779 · Published 3 Nov 2026 ]
Vulnerability in Effect-TS effect
[ Description ]Official description
Effect is a TypeScript framework that consists of several packages that work together to help build TypeScript applications. From @effect/platform 0.1.0 until 0.97.1 and effect 4.0.0-beta.0 until 4.0.0-beta.103, the name, domain, and path fields passed to makeCookie() allow semicolon delimiters that serializeCookie() writes verbatim into Set-Cookie headers. A caller that supplies attacker-controlled values can append cookie attributes, including a broader Domain or, when the caller has not set those options itself, SameSite=None or Max-Age. Encoded cookie values and CR or LF characters remain unaffected. This can widen a cookie's scope or add otherwise-unset cookie attributes. This issue is fixed in @effect/platform 0.97.1 and effect 4.0.0-beta.103.
[ Fixes ]Fixes and patches
No fix or interim patch is linked from our sources yet. Check the vendor references below and limit exposure of affected systems until a fix is available.
[ References ]References
- github.com/Effect-TS/effect/commit/4a57af24011db1d66e947289d2f7ffc2074696d2
- github.com/Effect-TS/effect/commit/5859b373b9be04d5037a594196b4743ad80379bd
- github.com/Effect-TS/effect/pull/6763
- github.com/Effect-TS/effect/pull/6765
- github.com/Effect-TS/effect/releases/tag/@effect/platform@0.97.1
- github.com/Effect-TS/effect/releases/tag/effect@4.0.0-beta.103
- github.com/Effect-TS/effect/security/advisories/GHSA-chp3-j5qr-2vfr