Out-of-bounds write in Linux kernel - CVE-2026-74610

Vulnerability details

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to an out-of-bounds write in tls_sw_sendmsg_locked() and the plaintext sk_msg ring handling in net/tls/tls_sw.c when processing sendmsg and later splice operations on a loopback TCP socket with the "tls" ULP attached. A local user can trigger the ring to appear empty after wrapping and overwrite live entries to cause a denial of service.

The issue can lead to a kernel NULL pointer dereference when a full plaintext sk_msg ring is left unpushed.

Affected software

How to mitigate CVE-2026-74610

External References

• https://git.kernel.org/stable/c/3c5f8f2aa57c647b83add4896aab64aac5fdedad
• https://git.kernel.org/stable/c/3fc5044796dd87b8d68be4207046f5ce2748174c
• https://git.kernel.org/stable/c/7bca91d63341274e857f4aeaad54d229405e93dc
• https://git.kernel.org/stable/c/aa8b14647721b5a4958712b35cf43e3125d47753
• https://git.kernel.org/stable/c/f634289a0b557a197c5f37284b623cefedfe73d5

Related Security Bulletins

• Out-of-bounds write in Linux kernel tls
• Debian update for linux