xfrm: Fix dev use-after-free in xfrm async resumption
CVE-2026-72463 · published 15 Aug 2026
How serious is it
- Severity: critical, CVSS score 9.8 out of 10.
- No exploit prediction (EPSS) score yet.
- Not on the CISA list of exploited vulnerabilities.
- No public exploit in Exploit-DB.
Is your app affected by CVE-2026-72463?
Paste this prompt into Claude Code, Cursor or any AI coding tool: it runs a free Shippable scan of your project and fixes what it finds. Built with Lovable, Bolt or v0? Scan your live app. Or upload your package file.
Who is affected
- Linux Linux: 4236c30b437b80f673b9e08c8fae38b8d471ac9e to < fed4d3195a31125566876952ce66113ec1eb9008, 0f451b43c88bf2b9c038b414be580efee42e031b to < 1acd93259b6be269e26be5d71c224bccd1f8352f, 1c428b03840094410c5fb6a5db30640486bbbfcb to < 63a30015199912bd5055bead8001b1ae68a67cdb, 1c428b03840094410c5fb6a5db30640486bbbfcb to < 8045c0df98d4f14c54e5cb875f1c9c0ce89fe4ff
- Linux Linux: 7.0
How to check
- Find out whether you run the affected product and which version, then compare it with the versions above.
How to fix
Copies a prompt for Claude Code, Cursor or Codex that asks it to check whether you run this product.
- Apply the vendor's update or mitigation from the references below. If there is none yet, limit exposure of the affected service until there is.
- If a vulnerable version was live, check your logs and rotate the secrets that server could read.
The advisory
In the Linux kernel, the following vulnerability has been resolved:
xfrm: Fix dev use-after-free in xfrm async resumption
xfrm async resumption hold skb->dev refcnt until after transport_finish.
However, xfrm_rcv_cb may modify skb->dev to tunnel dev without taking
device reference, such as vti_rcv_cb. The subsequent async resumption
will decrement the tunnel device's reference count, which lead to uaf
of tunnel dev and refcnt leak of orig dev as below:
unregister_netdevice: waiting for vti1 to become free. Usage count = -2
Stash the original skb->dev to fix refcnt imbalance. The new skb->dev set
by xfrm_rcv_cb can race with device teardown. Extend rcu protection over
xfrm_rcv_cb and transport_finish to prevent races.
Check your whole app
Dependencies are only half of it. Free and read-only: before you push, run npx shippable-dev scan localhost:3000 in your project folder, no account needed. For your live app, you prove it's yours with a one-line tag first.
References
- git.kernel.org/stable/c/fed4d3195a31125566876952ce66113ec1eb9008
- git.kernel.org/stable/c/1acd93259b6be269e26be5d71c224bccd1f8352f
- git.kernel.org/stable/c/63a30015199912bd5055bead8001b1ae68a67cdb
- git.kernel.org/stable/c/8045c0df98d4f14c54e5cb875f1c9c0ce89fe4ff
Merged from CVE List. Last updated 25 Oct 2026. All vulnerabilities · RSS · JSON