linux linux-kernel CVE-2026-80890 is a vulnerability in Linux Kernel
Published on September 4, 2026

sctp: reject stale cookies with mismatched verification tags
In the Linux kernel, the following vulnerability has been resolved: sctp: reject stale cookies with mismatched verification tags sctp_unpack_cookie() skips cookie expiration checks whenever an association already exists. This is broader than the exception in RFC 9260 Section 5.2.4. For an existing association, Section 5.2.4 permits an expired State Cookie only when both Verification Tags in the cookie match the current association. Otherwise, the packet SHOULD be discarded and a Stale Cookie ERROR MUST be sent. The broad check lets an expired Action A restart cookie reach sctp_sf_do_dupcook_a(). In a runtime test with the default 60 second cookie lifetime, replaying such a cookie after 65 seconds returned a COOKIE-ACK and restarted the association. Check cookie expiration unless both Verification Tags match. This preserves the Action D exception for a lost COOKIE ACK while rejecting expired cookies in all other cases.

NVD


Products Associated with CVE-2026-80890

Want to know whenever a new CVE is published for Linux Kernel? stack.watch will email you.

 

Affected Versions

Linux: Linux: