CVE-2026-31663
What it is
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.
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
- 0.2% 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: 0.2% in the next 30 days (EPSS).
- Severity: 7.8 HIGH (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.2% · EPSS, next 30 days
- Weakness
- CWE-416 · Use after free
- Record status
- Modified
Affected
- Linux Kernel < 3.3
- Linux Kernel < 3.17
- Linux Kernel < 4.15
- Linux Kernel < 6.18.23
- Linux Kernel < 6.19.13
- Linux Kernel 4.15
- 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-2026-31663.md and follow it. Check whether this project is affected by CVE-2026-31663. 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/0f451b43c88bf2b9c038b414be580efee42e031b
- https://git.kernel.org/stable/c/1c428b03840094410c5fb6a5db30640486bbbfcb
- https://git.kernel.org/stable/c/5002beda5cac69d522dc54da0d5d463ed9c963d2
References
- https://git.kernel.org/stable/c/0f451b43c88bf2b9c038b414be580efee42e031b
- https://git.kernel.org/stable/c/1c428b03840094410c5fb6a5db30640486bbbfcb
- https://git.kernel.org/stable/c/4236c30b437b80f673b9e08c8fae38b8d471ac9e
- https://git.kernel.org/stable/c/4d06caedea587c59cc2cc893ceecc57c75c64312
- https://git.kernel.org/stable/c/5002beda5cac69d522dc54da0d5d463ed9c963d2
- https://git.kernel.org/stable/c/94439cbe478b53f92223da9aae95fffb28623c3f
- https://access.redhat.com/errata/RHSA-2026:67471
- https://access.redhat.com/errata/RHSA-2026:68531
- https://access.redhat.com/errata/RHSA-2026:68532
- https://access.redhat.com/errata/RHSA-2026:68570
- https://access.redhat.com/security/cve/CVE-2026-31663
- https://bugzilla.redhat.com/show_bug.cgi?id=2461462
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-31663.json