CVE-2026-88038 — cookies vulnerable to Set-Cookie attribute injection via unvalidated domain and path options
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 …
Published: 2026-09-10 · CVSS: 4.8 · CVSS 3.1
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7