Vulnerability in Linux

CVE-2026-31663

In the Linux kernel, the following vulnerability has been resolved: xfrm: hold dev ref until after transport_finish NF_HOOK After async crypto completes, xfrm_input_resume() calls dev_put() immediately on re-entry before the skb reaches transport_finish. The skb->dev pointer is then used inside NF_HOOK and its okfn, which can race with device teardown. Remove the dev_put from the async resumption entry and instead drop the reference after the NF_HOOK call in transport_finish, using a saved device pointer since NF_HOOK may consume the skb. This covers NF_DROP, NF_QUEUE and NF_STOLEN paths that skip the okfn. For non-transport exits (decaps, gro, drop) and secondary async return points, release the reference inline when async is set.

EPSS: 0.001 (2.4th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

  • Linux — versions 3.16.55, e095ecaec6d94aa2156cceb98a85d409b51190f3, 4.15
  • Linux Linux_kernel — versions 4.15, 7.0

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-31663?
CVE-2026-31663 is a high-severity vulnerability in Linux, classified under CWE-826. CVSS score: 7.8/10. Published 2026-04-24.
How severe is CVE-2026-31663?
High severity. CVSS v3 base score is 7.8 out of 10.