CVE-2026-63912
What it is
In the Linux kernel, the following vulnerability has been resolved: xfrm: esp: restore combined single-frag length gate The ESP out-of-place fast path appends the trailer in esp_output_head() before esp_output_tail() allocates the destination page frag. The head-side gate currently checks skb->data_len and tailen separately, but the tail code allocates a single destination frag from the combined post-trailer skb->data_len. Reject the page-frag fast path when the combined aligned length exceeds a page. Otherwise skb_page_frag_refill() may fall back to a single page while the destination sg still spans the combined skb->data_len. Restore this combined-length page gate for both IPv4 and IPv6.
At a glance
- Exploitability
- Can be exploited over the network without logging in. High risk of data exposure, data tampering, service disruption.
- Exploit odds
- 0.7% 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: 0.7% in the next 30 days (EPSS).
- Severity: 9.8 CRITICAL (CVSS).
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Exploit probability
- 0.7% · EPSS, next 30 days
- Weakness
- CWE-125 · Out-of-bounds read
- Record status
- Analyzed
Affected
- Linux Kernel < 4.15
- Linux Kernel < 4.20
- Linux Kernel < 5.5
- Linux Kernel < 5.10.259
- Linux Kernel < 5.15.210
- Linux Kernel < 5.18
- Linux Kernel < 6.1.176
- Linux Kernel < 6.6.143
Attack profile CVSS 3.1 · 9.8
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Raw vector
CVSS:3.1/AV:N/AC:L/PR:N/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-2026-63912.md and follow it. Check whether this project is affected by CVE-2026-63912. 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/322e48187e0245ab2fff6fec2220b0cae677dbec
- https://git.kernel.org/stable/c/36519e3d941fc99d3b52c134dbaf311f987a4708
- https://git.kernel.org/stable/c/566295735530ee513326049b0540f32ec050bf2e
- https://git.kernel.org/stable/c/5d7ab86e2b6bc23054616bf6ac562013bf60af8c
- https://git.kernel.org/stable/c/65f3b3fc2347b89fe21db1e92c7681368415f095
- https://git.kernel.org/stable/c/b84091ceddc9f133229dceab3ccc930bf27f9cba
- https://git.kernel.org/stable/c/c093468aea8277f77272a4f199b2e15e19cabb59
- https://git.kernel.org/stable/c/dfa0d7b0ff1eb6b2c416b8fdb9b4f2cefba57a40
References
- https://git.kernel.org/stable/c/322e48187e0245ab2fff6fec2220b0cae677dbec
- https://git.kernel.org/stable/c/36519e3d941fc99d3b52c134dbaf311f987a4708
- https://git.kernel.org/stable/c/566295735530ee513326049b0540f32ec050bf2e
- https://git.kernel.org/stable/c/5d7ab86e2b6bc23054616bf6ac562013bf60af8c
- https://git.kernel.org/stable/c/65f3b3fc2347b89fe21db1e92c7681368415f095
- https://git.kernel.org/stable/c/b84091ceddc9f133229dceab3ccc930bf27f9cba
- https://git.kernel.org/stable/c/c093468aea8277f77272a4f199b2e15e19cabb59
- https://git.kernel.org/stable/c/dfa0d7b0ff1eb6b2c416b8fdb9b4f2cefba57a40