CVE-2026-64123

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

Description A slab-use-after-free issue exists in the High-availability Seamless Redundancy (HSR) implementation. The hsr->node db is accessed by generic-netlink operations under rcu read lock() via the hsr get next node() and hsr get node data() functions. However, the RTM DELLINK teardown process removes the node table using list del() and frees each node immediately. This allows a reader to hold a struct hsr node pointer after hsr dellink() has been called, leading to a use-after-free when accessing node->macaddress A.

Recommendations Update the Linux kernel to a version where list del rcu() is used and the free operation is deferred through the hsr free node rcu() callback.