CVE-2026-31474
What it is
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.
At a glance
- Exploitability
- Can be exploited locally on the machine with a low-privilege account. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.1% chance of exploitation in the next 30 days (EPSS).
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: 0.1% in the next 30 days (EPSS).
- Severity: 7.8 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.1% · EPSS, next 30 days
- Weakness
- CWE-416 · Use after free
- Record status
- Modified
Affected
- Linux Kernel < 6.6.131
- Linux Kernel < 6.12.80
- Linux Kernel < 6.18.21
- Linux Kernel < 6.19.11
- Linux Kernel 6.4
- Linux Kernel 7.0
Attack profile CVSS 3.1 · 7.8
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-31474.md and follow it. Check whether this project is affected by CVE-2026-31474. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
Fix and advisories
- https://git.kernel.org/stable/c/2e62e7051eca75a7f2e3d52d62ec10d7d7aa358c
- https://git.kernel.org/stable/c/424e95d62110cdbc8fd12b40918f37e408e35a92
- https://git.kernel.org/stable/c/9649d051e54413049c009638ec1dc23962c884a4
- https://git.kernel.org/stable/c/cb3d6efa78460e6d50bf68806d0db66265709f64
- https://git.kernel.org/stable/c/eec8a1b18a79600bd4419079dc0026c1db72a830
References
- https://git.kernel.org/stable/c/2e62e7051eca75a7f2e3d52d62ec10d7d7aa358c
- https://git.kernel.org/stable/c/424e95d62110cdbc8fd12b40918f37e408e35a92
- https://git.kernel.org/stable/c/9649d051e54413049c009638ec1dc23962c884a4
- https://git.kernel.org/stable/c/cb3d6efa78460e6d50bf68806d0db66265709f64
- https://git.kernel.org/stable/c/eec8a1b18a79600bd4419079dc0026c1db72a830
- https://access.redhat.com/errata/RHSA-2026:27288
- https://access.redhat.com/errata/RHSA-2026:27731
- https://access.redhat.com/errata/RHSA-2026:27789
- https://access.redhat.com/security/cve/CVE-2026-31474
- https://bugzilla.redhat.com/show_bug.cgi?id=2460646
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-31474.json