Improper input validation in Linux kernel - CVE-2026-74308
Published: August 15, 2026
Vulnerability details
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to improper state validation in ext4_journalled_write_end() and ext4_write_inline_data_end() when handling writes on an ext4 filesystem mounted with the data=journal option after a failed inline-data-to-extent conversion. A local user can trigger a crafted write operation to cause a denial of service.
The issue can be triggered when a previous attempt to convert inline data to an extent fails, such as due to insufficient space.
Affected software
Ubuntu
linux-gcp-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
How to mitigate CVE-2026-74308
linux-gcp-7.0 (Ubuntu package) - addressed in versions 7.0.0-38.38~24.04.4, 7.0.0-1013.13~24.04.1, 7.0.0-1014.14~24.04.1
linux-azure-7.0 (Ubuntu package) - addressed in versions 7.0.0-1016.16~24.04.1, 7.0.0-1017.17~24.04.1
External References
- https://git.kernel.org/stable/c/0ae42b51607240990614e0843f0d3529aaff62cc
- https://git.kernel.org/stable/c/260830a9a706f5d335398236fc788ce32f220de1
- https://git.kernel.org/stable/c/9808ae9fae996afa942bd963a39c9b1cdeebd0bd
- https://git.kernel.org/stable/c/ad09aa45965d3fafaf9963bc78109b73c0f9ac8d
- https://git.kernel.org/stable/c/f00f5c0dd55319bc33b76f72c853bda0e0a32eda