SB2026091980 - Use-after-free in Linux kernel fuse
Published: September 19, 2026
Security Bulletin ID
SB2026091980
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Use-after-free (CVE-ID: CVE-2026-90140)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 5.6 [CVSS:4.0/AV:L/AC:L/AT:P/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local privileged user to cause a denial of service.
The vulnerability exists due to a use-after-free in the cuse module's pending RCU callback handling when unloading the cuse module while a fuse connection release callback remains pending. A local privileged user can close /dev/cuse and unload the cuse module before the callback executes to cause a denial of service.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/389bd349ddbcf90dbd8a4f2a4ab6e552d53df134
- https://git.kernel.org/stable/c/45ae914b2f6ea56fc2f1c017fdee4e995bcb4c0e
- https://git.kernel.org/stable/c/4deb3edead0c0e172cc7349e8855d741d3c5e162
- https://git.kernel.org/stable/c/7fe415e1cd8fa875be263670c0ab47109818abb6
- https://git.kernel.org/stable/c/a1b46aee33d83f14ed62d7fdef1a91d3e0b732a9
- https://git.kernel.org/stable/c/ac5c499413385cea3e0220d6050408d50842891d
- https://git.kernel.org/stable/c/c40f3f24839f8404325a2099e26c2a04786ae309