Race condition in Linux kernel - CVE-2026-64119
Published: July 20, 2026
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper concurrent modification of an rcu-protected list in l2tp_session_unhash() when handling concurrent L2TP session get, create, and delete operations on the same tunnel. A local user can issue crafted concurrent netlink commands to cause a denial of service.
Exploitation can pin a host CPU indefinitely and stall RCU grace periods, and the issue is reachable from a standard unshare sandbox when l2tp_core is loaded.
Affected software
Ubuntu
linux-ibm (Ubuntu package)
linux-azure (Ubuntu package)
linux-aws (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-nvidia-bos (Ubuntu package)
How to mitigate CVE-2026-64119
linux-ibm (Ubuntu package) - addressed in versions 7.0.0-1008.8, 7.0.0-1010.10
linux-azure (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1010.10
linux-aws (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1015.15
linux-nvidia (Ubuntu package) - addressed in versions 7.0.0-1016.16, 7.0.0-1016.16~24.04.1
linux-nvidia-bos (Ubuntu package) - update to 7.0.0-2016.16