NULL pointer dereference in Linux kernel - CVE-2025-71295
Published: May 7, 2026
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to a null pointer dereference in try_to_free_buffers() when releasing a folio belonging to a mapping with AS_RELEASE_ALWAYS set but no release_folio operation defined. A local user can trigger this code path to cause a denial of service.
The issue occurs when the folio has no buffers attached.
Affected software
Ubuntu
linux (Ubuntu package)
linux-azure-fips (Ubuntu package)
linux-hwe-6.8 (Ubuntu package)
linux-nvidia-tegra (Ubuntu package)
linux-aws-6.8 (Ubuntu package)
linux-raspi (Ubuntu package)
linux-azure-fde (Ubuntu package)
linux-azure-fde-6.8 (Ubuntu package)
linux-azure (Ubuntu package)
linux-raspi-realtime (Ubuntu package)
How to mitigate CVE-2025-71295
linux (Ubuntu package) - addressed in versions 6.8.0-134.134, 6.8.0-1057.58~22.04.1, 6.8.0-1058.61+fips1, 6.8.0-1058.61~22.04.1, 6.8.0-1060.61, 6.8.0-1060.63+fips1, 6.8.0-1060.63~22.04.1, 6.8.0-1063.69, 6.8.0-1063.69+fips1, 6.8.1-1055.56, 6.8.1-1055.56~22.04.1
linux-azure-fips (Ubuntu package) - addressed in versions 6.8.0-134.134+fips1, 6.8.0-1062.69+fips1
linux-hwe-6.8 (Ubuntu package) - update to 6.8.0-136.136~22.04.1
linux-nvidia-tegra (Ubuntu package) - update to 6.8.0-1029.30
linux-aws-6.8 (Ubuntu package) - addressed in versions 6.8.0-1045.48, 6.8.0-1057.58~22.04.1, 6.8.0-1058.61.1, 6.8.0-1058.64, 6.8.0-1060.61~22.04.1, 6.8.0-1060.63~22.04.1, 6.8.0-1063.69~22.04.1
linux-raspi (Ubuntu package) - update to 6.8.0-1060.64
linux-azure-fde (Ubuntu package) - update to 6.8.0-1062.69
linux-azure-fde-6.8 (Ubuntu package) - update to 6.8.0-1062.69~22.04.1
linux-azure (Ubuntu package) - addressed in versions 6.8.0-1063.71, 6.8.0-1063.71~22.04.1
linux-raspi-realtime (Ubuntu package) - update to 6.8.0-2049.50
External References
- https://git.kernel.org/stable/c/1b111a69a6e33a922622bf9870e4e63fb2b649c8
- https://git.kernel.org/stable/c/42c32d7571ccd8ef32351cac506f00b0fae99fd2
- https://git.kernel.org/stable/c/727e5140e0cf83b4ce6a11b89bb73bff5d96f8f3
- https://git.kernel.org/stable/c/b68f91ef3b3fe82ad78c417de71b675699a8467c
- https://git.kernel.org/stable/c/c1b6227555c52781178132b7a06466711855795c
- https://git.kernel.org/stable/c/c6246ca15999053d2632fbcc7b86e6eef7f077cb
Related Security Bulletins
- NULL pointer dereference in Linux kernel fs
- Ubuntu update for linux
- Ubuntu update for linux-nvidia-tegra
- Ubuntu update for linux-aws-6.8
- Ubuntu update for linux-raspi-realtime
- Ubuntu update for linux-raspi
- Ubuntu update for linux-azure-fips
- Ubuntu update for linux-azure-fde-6.8
- Ubuntu update for linux-azure-fde
- Ubuntu update for linux-azure
- Ubuntu update for linux-hwe-6.8