CVE-2026-115779 json
Effect: Cookie attribute injection via domain, path, and name fields in @effect/platform makeCookie()
published 6d ago modified 6d ago also EUVD-2026-116496
- cvss
- 6.3
- version 4.0, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 50%
- public exploits
- 0
- none known
Summary
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.
Patch / fix
- github.com/Effect-TS/effect@4a57af2 commit
- github.com/Effect-TS/effect@5859b37 commit
- github.com/Effect-TS/effect#6763 pull request
- github.com/Effect-TS/effect#6765 pull request
- github.com/Effect-TS/effect/releases/tag/@effect/platform@0.97.1 release
- github.com/Effect-TS/effect/releases/tag/effect@4.0.0-beta.103 release
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Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 6d ago
Exploit prediction
0.63% chance of exploitation in the next 30 days, higher than 50% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 6.3 | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N |
| CNA | 4.0 | 6.3 | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- Effect-TS effect
- @effect platform
Classification
- Weakness
-
- CWE-74 Improper Neutralization of Special Elements in Output Used by a Downstream Component
References
- github.com /Effect-TS/effect/pull/6763
- github.com /Effect-TS/effect/pull/6765
- github.com /Effect-TS/effect/commit/4a57af24011db1d66e947289d2f7ffc2074696d2
- github.com /Effect-TS/effect/commit/5859b373b9be04d5037a594196b4743ad80379bd
- github.com /Effect-TS/effect/security/advisories/GHSA-chp3-j5qr-2vfr
- 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
Sources
- CVE List CVE-2026-115779
- NVD CVE-2026-115779
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.