Race condition in Linux kernel - CVE-2026-64093
Published: July 20, 2026
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a race condition in batman-adv tp_meter timer handling in batadv_tp_sender_cleanup() when shutting down the sender timer during cleanup. A local user can trigger timer re-arming after cleanup to cause a denial of service.
The issue occurs because the timer may be re-armed after its reference has already been released.
Affected software
Ubuntu
linux (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-oracle-5.15 (Ubuntu package)
linux-gcp-5.15 (Ubuntu package)
linux-gcp (Ubuntu package)
linux-gke (Ubuntu package)
linux-nvidia-tegra (Ubuntu package)
linux-azure (Ubuntu package)
linux-ibm (Ubuntu package)
linux-aws (Ubuntu package)
linux-oracle-7.0 (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
linux-nvidia-bos (Ubuntu package)
How to mitigate CVE-2026-64093
linux (Ubuntu package) - addressed in versions 5.15.0-195.205~20.04.1, 5.15.0-195.205, 5.15.0-198.208~20.04.1, 5.15.0-198.208+fips1, 5.15.0-1080.84, 5.15.0-1100.108, 5.15.0-1109.111, 5.15.0-1109.114, 5.15.0-1111.115~20.04.1, 5.15.0-1111.115, 5.15.0-1112.118~20.04.1, 5.15.0-1112.118, 5.15.0-1113.119, 5.15.0-1114.120, 5.15.0-1116.125~20.04.1, 5.15.0-1117.124~20.04.1, 5.15.0-1117.124, 5.15.0-1117.124+fips1, 5.15.0-1122.131~20.04.1, 5.15.0-1123.132~20.04.1, 5.15.0-1123.132, 5.15.0-1123.132+fips1, 5.15.0.195.160, 5.15.0.195.205~20.04.1, 5.15.0.198.114, 5.15.0.198.171, 5.15.0.198.208~20.04.1, 5.15.0.1080.83~20.04.1, 5.15.0.1100.99, 5.15.0.1109.105, 5.15.0.1109.113, 5.15.0.1111.108, 5.15.0.1111.115~20.04.1, 5.15.0.1112.111, 5.15.0.1112.118~20.04.1, 5.15.0.1113.112, 5.15.0.1114.110, 5.15.0.1116.120, 5.15.0.1117.113, 5.15.0.1117.120, 5.15.0.1117.124~20.04.1, 5.15.0.1122.131~20.04.1, 5.15.0.1123.107, 5.15.0.1123.121, 5.15.0.1123.132~20.04.1
linux-nvidia (Ubuntu package) - addressed in versions 5.15.0-1112.113, 5.15.0.1112.112, 7.0.0-1016.16~24.04.1, 7.0.0-1016.16
linux-oracle-5.15 (Ubuntu package) - addressed in versions 5.15.0-1114.120~20.04.1, 5.15.0.1114.120~20.04.1
linux-gcp-5.15 (Ubuntu package) - addressed in versions 5.15.0-1118.128~20.04.1, 5.15.0.1118.128~20.04.1
linux-gcp (Ubuntu package) - addressed in versions 5.15.0-1118.128, 5.15.0-1118.128+fips1, 5.15.0.1118.107, 5.15.0.1118.115, 6.8.0-1070.78
linux-gke (Ubuntu package) - addressed in versions 6.8.0-146.146.1~22.04.1, 6.8.0-146.146.1, 6.8.0-1051.55, 6.8.0-1063.66, 6.8.0-1064.67~22.04.1, 6.8.0-1064.67, 6.8.0-1064.67.1, 6.8.0-1065.73, 6.8.0-1066.67
linux-nvidia-tegra (Ubuntu package) - update to 6.8.0-1035.38
linux-azure (Ubuntu package) - addressed in versions 6.8.0-1068.75~22.04.1, 6.8.0-1068.75, 6.8.0-1069.77+fips1, 6.8.0-1070.78~22.04.1, 6.8.0-1070.78, 7.0.0-1009.9, 7.0.0-1010.10
linux-ibm (Ubuntu package) - addressed in versions 7.0.0-1008.8, 7.0.0-1010.10
linux-aws (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1015.15
linux-oracle-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-gcp-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-azure-7.0 (Ubuntu package) - update to 7.0.0-1014.14~24.04.1
linux-nvidia-bos (Ubuntu package) - update to 7.0.0-2016.16
External References
- https://git.kernel.org/stable/c/00bf4bb9947b1190a8be8d9b6a1bcbfa3707785c
- https://git.kernel.org/stable/c/5bc2d50fb66b46f86543d5153a188eb1486d0b6e
- https://git.kernel.org/stable/c/74a76634055462833446684fd526d73c290ea43a
- https://git.kernel.org/stable/c/770bf0a35f0620b526fd4193889d1e77084e4c43
- https://git.kernel.org/stable/c/933880a8bc9b4042223a79255c0b1021cdc36991
- https://git.kernel.org/stable/c/d5487249a81ea658717614009c8f46acc5b7101a
- https://git.kernel.org/stable/c/f86b20ec8d17d77bddc02c5c86cfa2389d84ecff
Related Security Bulletins
- Race condition in Linux kernel batman-adv
- Ubuntu update for linux-ibm
- Ubuntu update for linux-azure
- Ubuntu update for linux-aws
- Ubuntu update for linux-nvidia-bos
- Ubuntu update for linux-nvidia
- Ubuntu update for linux-gcp-7.0
- Ubuntu update for linux-oracle-7.0
- Ubuntu update for linux-azure-7.0
- Ubuntu update for linux-nvidia-tegra
- Ubuntu update for linux-gcp
- Ubuntu update for linux-gke
- Ubuntu update for linux-nvidia
- Ubuntu update for linux-azure
- Ubuntu update for linux-gcp
- Ubuntu update for linux-gcp-5.15
- Ubuntu update for linux-oracle-5.15
- Ubuntu update for linux