SB20260812401 - Use-after-free in Linux kernel iucv
Published: August 12, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Use-after-free (CVE-ID: CVE-2026-68140)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 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]
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to use-after-free in the af_iucv message queue handling when processing queued message notifications after a connection is severed. A local user can trigger connection severing with queued notifications still pending and then invoke recvmsg() to cause a denial of service.
The issue occurs because queued notifications retain stale references to a freed iucv_path.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/23658b350b4107e8292045c2044983fd426fa15d
- https://git.kernel.org/stable/c/900cd6d8119b7f3ae5c4bf82f922ff5957df43db
- https://git.kernel.org/stable/c/a5bbaddf69853117f28173c3f5c8fc14c6b2ec82
- https://git.kernel.org/stable/c/be7cc4656eb1f54029610e82d1f0fdd3f9b5ec0a
- https://git.kernel.org/stable/c/f579582c03ed526281a8450159baf1d35099a85f