SB20261106121 - Use-after-free in Linux kernel block xen-blkback driver
Published: November 6, 2026
Security Bulletin ID
SB20261106121
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-2026-100082)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to use-after-free in the Linux kernel xen-blkback driver when reading I/O statistics via sysfs concurrently with frontend device teardown. A local user can read statistics while the underlying data is being freed to potentially trigger a kernel crash and cause a denial of service.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/253cff0526781e28b1b0f9fdacd74ecdc23d3ab7
- https://git.kernel.org/stable/c/2c9ccbe0ffcff3615c7ad917c49b67571a41f21c
- https://git.kernel.org/stable/c/58ba056991dbcec8a75e6861cb4479ac947b69e6
- https://git.kernel.org/stable/c/b0378161c28e77e4d0e2eda3c9433ab4394d2a2f
- https://git.kernel.org/stable/c/b764e17313534794aeb99c901869f213e36a16ef
- https://git.kernel.org/stable/c/c49934da934cf495faf782aa5d84f413221c9be6
- https://git.kernel.org/stable/c/fe9ead8c5bdb752e329cecfecbdb5dfca5e9996b
- http://www.openwall.com/lists/oss-security/2026/11/06/11
- http://xenbits.xen.org/xsa/advisory-528.html