SB20260824241 - Use-after-free in Linux kernel ipv4
Published: August 24, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Use-after-free (CVE-ID: CVE-2026-74589)
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 tcp_bpf_send_verdict() and tcp_bpf_sendmsg_redir() when processing concurrent sendmsg() operations with a cached redirect verdict. A local user can trigger concurrent socket send operations to cause a denial of service.
The issue occurs when apply_bytes keeps the cached verdict active, allowing one thread to release the redirect socket reference while another thread still uses a stale pointer.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/1cec526cf0a2227395f2c2f4b671cb052ff0b00e
- https://git.kernel.org/stable/c/41b7da0cb72ca5aa1e62b68dab323d0791fc6bdf
- https://git.kernel.org/stable/c/4c9d9aa809c261dc0490a0e19d675f7e8e4c85bf
- https://git.kernel.org/stable/c/90a19b0894ba79a699b48cf44421b36fbd566e99
- https://git.kernel.org/stable/c/9b4fbc371a6ecf1b4e43b5a629015cc0830d8de3
- https://git.kernel.org/stable/c/a14e4ef1d90c3418f01b3b6b8fd3a40a0a208a10
- https://git.kernel.org/stable/c/a76624733730e541e4955fdecf506af2f6b20558
- https://git.kernel.org/stable/c/d192cff2a37d59206dabe6ec2e60ceac6271f274