VULNERABILITY INTELLIGENCE

CVE-2026-31474

CVSS score7.8 HIGH
EPSS probability0.10%
CISA KEVNot currently listed
Published2026-04-22
Last modified2026-10-19
CVSS vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Description

In the Linux kernel, the following vulnerability has been resolved: can: isotp: fix tx.buf use-after-free in isotp_sendmsg() isotp_sendmsg() uses only cmpxchg() on so->tx.state to serialize access to so->tx.buf. isotp_release() waits for ISOTP_IDLE via wait_event_interruptible() and then calls kfree(so->tx.buf). If a signal interrupts the wait_event_interruptible() inside close() while tx.state is ISOTP_SENDING, the loop exits early and release proceeds to force ISOTP_SHUTDOWN and continues to kfree(so->tx.buf) while sendmsg may still be reading so->tx.buf for the final CAN frame in isotp_fill_dataframe(). The so->tx.buf can be allocated once when the standard tx.buf length needs to be extended. Move the kfree() of this potentially extended tx.buf to sk_destruct time when either isotp_sendmsg() and isotp_release() are done.

Weakness classification

  • nvd@nist.gov: CWE-416
  • 134c704f-9b21-4f2e-91b3-4a467353bcc0: CWE-416
  • 0b0ca135-0b70-47e7-9f44-1890c2a1c46c: CWE-364

Primary references