Use-after-free in Linux kernel - CVE-2026-74348

Vulnerability identifier: #VU142851

CSH Severity: Low

CVSS v4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

CVE-ID: CVE-2026-74348

CWE-ID: CWE-416

Exploitation vector: Local access

Exploit availability: No public exploit available

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to a use-after-free in the ocfs2 dlm locking_state debugfs open and release handling when opening the locking_state debugfs file during concurrent domain teardown. A local user can open and later close the debugfs file to cause a denial of service.

The issue occurs when the open path stores a raw dlm_ctxt pointer even if acquiring a reference fails, and the release path later accesses that context after it has been freed.

Linux kernel
Ubuntu
linux-nvidia (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux (Ubuntu package)
linux-oem-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
linux-azure (Ubuntu package)

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
linux-nvidia (Ubuntu package) - addressed in versions 5.15.0-1112.113, 5.15.0.1112.112
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 (Ubuntu package) - addressed in versions 7.0.0-38.38, 7.0.0-38.38.1, 7.0.0-1008.9, 7.0.0-1013.13~24.04.1, 7.0.0-1014.14, 7.0.0-1015.15
linux-oem-7.0 (Ubuntu package) - update to 7.0.0-1015.15
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
linux-azure (Ubuntu package) - addressed in versions 7.0.0-1016.16, 7.0.0-1017.17

• https://git.kernel.org/stable/c/03ad858ce8064861ea580021976dc19b7aabb549
• https://git.kernel.org/stable/c/5bee5d5f67aedd26d2b72e00e49dd93331fbcc30
• https://git.kernel.org/stable/c/6cc93dea4078cbcddee63fa2234e382a76600464
• https://git.kernel.org/stable/c/90a6512425414098a63fc97b77bed089c75d106b
• https://git.kernel.org/stable/c/9c81c1a61a52b6ecf0d14f1dbd95f154a7a9e92a
• https://git.kernel.org/stable/c/a087b2d3411e7f9df71ba3293596923ee2c70d65
• https://git.kernel.org/stable/c/a09831214912a1f270663d935613910fafd8d883
• https://git.kernel.org/stable/c/aa7883b6a3c76301a3299deb34de948e73bb6a08

• Use-after-free in Linux kernel ocfs2 dlm
• Ubuntu update for linux-gcp-7.0
• Ubuntu update for linux-nvidia
• Ubuntu update for linux-azure-7.0
• Ubuntu update for linux
• Ubuntu update for linux-azure
• Ubuntu update for linux-oem-7.0