CVE-2026-16729

Name of the Vulnerable Software and Affected Versions undici versions prior to 6.28.0 undici versions 7.0.0 through 7.28.9 undici versions 8.0.0 through 8.8.9

Description The setCookie() function fails to fully sanitize cookie attributes. Specifically, the domain value is not checked for semicolons and entries in the unparsed array are not sanitized. This allows attacker-influenced input to inject additional cookie attributes. For instance, a domain value containing a semicolon can append attributes like SameSite, and an unparsed entry can inject attributes such as HttpOnly without the caller's intent. Applications passing user-controlled input to these fields, such as reverse-proxy or multi-tenant servers scoping session cookies to tenant-supplied domains, may experience bypassed SameSite CSRF protections or have the Secure, HttpOnly, and SameSite attributes forced, stripped, or overridden.

Recommendations Update to version 6.28.0 Update to version 7.29.0 Update to version 8.9.0