SB20260812121 - Use-after-free in Linux kernel iucv
Published: August 12, 2026
Security Bulletin ID
SB20260812121
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-2026-68397)
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 a use-after-free in afiucv_hs_rcv() and the afiucv_hs_callback_* handlers when processing AF_IUCV socket traffic. A local user can trigger a concurrent socket close to cause a denial of service.
The issue arises because the destination socket is looked up under a lock and then used after the lock is released without holding a reference.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/1801cb20a5025a787d6853e19c38db138344b4b4
- https://git.kernel.org/stable/c/4dc0e63abf8bc7ba8892e617c1fb8b204361e022
- https://git.kernel.org/stable/c/4fa349156043dc119721d067329714179f501749
- https://git.kernel.org/stable/c/5595ea59cdf29182cf6a270cacc1426c57b603de
- https://git.kernel.org/stable/c/c75a950e77356e526672cba4584080c6c8b793b6