๐Ÿ” CVE Alert

CVE-2026-88038

MEDIUM 4.8

cookies vulnerable to Set-Cookie attribute injection via unvalidated domain and path options

CVSS Score
4.8
EPSS Score
0.0%
EPSS Percentile
0th

cookies is a Node.js library for reading and writing HTTP cookies, used by Koa via ctx.cookies. In versions before 0.9.2 the library validates the cookie name and value against character sets that reject the semicolon separator, but the domain and path options are checked only against a permissive RFC 7230 field-content matcher that allows semicolons, and both are written into the Set-Cookie header unescaped. An application that passes untrusted or request-derived data into the domain or path option can therefore inject additional cookie attributes, overriding SameSite, Secure, HttpOnly, or Domain on the cookies the application issues. This is a Set-Cookie attribute injection issue (CWE-74). The issue is fixed in cookies 0.9.2, which validates domain and path against RFC 6265 character sets. As a workaround, keep domain and path application-set rather than derived from untrusted input.

CWE CWE-74
Vendor cookies
Product cookies
Published Sep 10, 2026
Last Updated Sep 10, 2026
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CVSS v3 Breakdown

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability

Affected Versions

cookies / cookies
0 < 0.9.2

References

NVD โ†— CVE.org โ†— EPSS Data โ†—
github.com: https://github.com/pillarjs/cookies/security/advisories/GHSA-x44v-5gxf-r6hf cna.openjsf.org: https://cna.openjsf.org/security-advisories.html

Credits

UlisesGascon blakeembrey ๐Ÿ” Zelys-DFKH