Skip to content
CVE PROGRAM SOURCE RECORD7.8 High

CVE-2026-31474

can: isotp: fix tx.buf use-after-free in isotp_sendmsg()

Read JSON ↗CVE.org ↗
Status
Published
Published
Updated
Assigning organization
Linux

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.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

Linux Linux

Default version status: unaffected

  • 96d1c81e6a0478535342dff6c730adb076cd84e8 to < cb3d6efa78460e6d50bf68806d0db66265709f64affected
  • 96d1c81e6a0478535342dff6c730adb076cd84e8 to < 9649d051e54413049c009638ec1dc23962c884a4affected
  • 96d1c81e6a0478535342dff6c730adb076cd84e8 to < eec8a1b18a79600bd4419079dc0026c1db72a830affected
  • 96d1c81e6a0478535342dff6c730adb076cd84e8 to < 2e62e7051eca75a7f2e3d52d62ec10d7d7aa358caffected
  • 96d1c81e6a0478535342dff6c730adb076cd84e8 to < 424e95d62110cdbc8fd12b40918f37e408e35a92affected

Linux Linux

Default version status: affected

  • 6.4affected
  • 0 to < 6.4unaffected
  • 6.6.131 to ≤ 6.6.*unaffected
  • 6.12.80 to ≤ 6.12.*unaffected
  • 6.18.21 to ≤ 6.18.*unaffected
  • 6.19.11 to ≤ 6.19.*unaffected
  • 7.0 to ≤ *unaffected

References