Strix
26.1K

CVE-2026-63912

CRITICALCVSS 9.8/10EPSS 0.70%

Last modified

CVE-2026-63912 is a critical-severity vulnerability rated 9.8/10 on the CVSS scale. 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. EPSS estimates a 0.70% chance of exploitation in the next 30 days.

Description

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.

Metrics

CVSS 3.1
9.8/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability
0.70%

49.5th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Source: CNA advisory (CVE.org). NVD analysis pending.

VendorProductVersions
LinuxLinux>= c075c3ea031757f8ea2d34567565b61a868c08d5, < 566295735530ee513326049b0540f32ec050bf2e; >= a583f2f3c8788bffd7fd7baeb76bd6d80543d7ea, < 5d7ab86e2b6bc23054616bf6ac562013bf60af8c; >= 5bd8baab087dff657e05387aee802e70304cc813, < 36519e3d941fc99d3b52c134dbaf311f987a4708; >= 5bd8baab087dff657e05387aee802e70304cc813, < 322e48187e0245ab2fff6fec2220b0cae677dbec; >= 5bd8baab087dff657e05387aee802e70304cc813, < b84091ceddc9f133229dceab3ccc930bf27f9cba; >= 5bd8baab087dff657e05387aee802e70304cc813, < c093468aea8277f77272a4f199b2e15e19cabb59; >= 5bd8baab087dff657e05387aee802e70304cc813, < 65f3b3fc2347b89fe21db1e92c7681368415f095; >= 5bd8baab087dff657e05387aee802e70304cc813, < dfa0d7b0ff1eb6b2c416b8fdb9b4f2cefba57a40; 2c66b0c95bb0aa7652ba1eba293d0d5993b35a38; ef6f83df1209a7d9bd1c605a62457d4c00f9179e; 3defefd22ad5fbbe639b6157fb7e6311b2bf333d; b657030870bb5351c5b1e84d4e9f186da6ca0496; >= 5.10.113, < 5.10.259; >= 5.15.36, < 5.15.210; >= 4.14.288, < 4.15; >= 4.19.252, < 4.20; >= 5.4.205, < 5.5; >= 5.17.5, < 5.18
LinuxLinux5.18

References

Timeline

Published
Last Modified
Status
Awaiting Analysis

Frequently Asked Questions

What is CVE-2026-63912?
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.
How severe is CVE-2026-63912?
CVE-2026-63912 has a CVSS score of 9.8/10 (CRITICAL severity). The EPSS model estimates a 0.70% probability of exploitation in the next 30 days.
How do I fix CVE-2026-63912?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

How Strix Helps

Related CVEs from 2026

View all 2026CVEs →

Are you affected by CVE-2026-63912?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST