CVE-2026-80849

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description A use-after-free issue exists in the TCP Authentication Option (TCP-AO) implementation. The problem occurs during a reconnection to another peer when tcp inbound ao hash() is called. If a softirq updates the current key variable after the tcp ao connect init() function has already run its cleanup loop but before the RCU callback frees the key, current key is left pointing to freed memory. Subsequent transmissions using tcp get current key() and tcp ao transmit skb() then attempt to read the traffic key from this freed object. RCU (Read-Copy-Update) is a synchronization mechanism used to protect shared data from simultaneous access by multiple processors.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.