CVE-2026-56762

Hono before 4.12.12 does not validate cookie names on the write path in the setCookie, serialize, and serializeSigned functions, allowing invalid characters such as control characters e.g. \r or \n when an application passes a user-controlled cookie name. This can produce malformed Set-Cookie...

CVE-2026-56762

Hono CVE-2026-56762 affects Hono before 4.12.12, where cookie-name validation is missing on the write path in setCookie(), serialize(), and serializeSigned(). This allows invalid characters (e.g., control chars like \r/\n) in user-controlled cookie names, producing malformed Set-Cookie header val...

GHSA-26PP-8WGV-HJVM Hono missing validation of cookie name on write path in setCookie()

Summary Cookie names are not validated on the write path when using setCookie, serialize, or serializeSigned to generate Set-Cookie headers. While certain cookie attributes such as domain and path are validated, the cookie name itself may contain invalid characters. This results in inconsistent...