PT-2026-34379 · Linux · Linux Kernel

Published 2026-04-22 · Updated 2026-04-23 · CVE-2026-31474

Positive Technologies (AI Summary)

CVSS v3.1

7.8

High

Base vector

AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description A use-after-free issue exists in the isotp sendmsg() function. The function uses cmpxchg() on so->tx.state to serialize access to so->tx.buf. When isotp release() waits for ISOTP IDLE via wait event interruptible(), a signal can interrupt this process during a close() operation while tx.state is ISOTP SENDING. This causes the loop to exit prematurely, leading the release process to force ISOTP SHUTDOWN and call kfree(so->tx.buf) while isotp fill dataframe() may still be reading so->tx.buf for the final CAN frame.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Use After Free

Weakness Enumeration

CWE-416

Related Identifiers

CVE-2026-31474

Affected Products

Linux Kernel

References · 15

• https://security-tracker.debian.org/tracker/CVE-2026-31474 · Vendor Advisory
• https://git.kernel.org/stable/c/2e62e7051eca75a7f2e3d52d62ec10d7d7aa358c · Patch
• https://git.kernel.org/stable/c/cb3d6efa78460e6d50bf68806d0db66265709f64 · Patch
• https://git.kernel.org/stable/c/eec8a1b18a79600bd4419079dc0026c1db72a830 · Patch
• https://osv.dev/vulnerability/UBUNTU-CVE-2026-31474 · Vendor Advisory
• https://ubuntu.com/security/CVE-2026-31474 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-31474 · Security Note
• https://osv.dev/vulnerability/BELL-CVE-2026-31474 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2026-31474 · Vendor Advisory
• https://git.kernel.org/stable/c/424e95d62110cdbc8fd12b40918f37e408e35a92 · Patch
• https://git.kernel.org/stable/c/9649d051e54413049c009638ec1dc23962c884a4 · Patch
• https://cve.org/CVERecord?id=CVE-2026-31474 · Security Note
• https://twitter.com/CVEnew/status/2046980009772855384 · Twitter Post
• https://docs.bell-sw.com/security/cves/CVE-2026-31474 · Note
• https://git.kernel.org/linus/424e95d62110cdbc8fd12b40918f37e408e35a92 · Note