CVE-2026-63912

xfrm: esp: restore combined single-frag length gate

State: Published
Severity: 9.8 Critical
Published: Jul 19, 2026
Updated: Oct 19, 2026
Reserved: Jul 19, 2026

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.

Scores

CVSS	Score	Vector	Source
3.1	9.8 Critical	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	Linux

Weaknesses

CWE-125 Out-of-bounds Read

Affected Products

Product	Versions
LinuxLinux	c075c3ea031757f8ea2d34567565b61a868c08d5 to before 566295735530ee513326049b0540f32ec050bf2eAffected a583f2f3c8788bffd7fd7baeb76bd6d80543d7ea to before 5d7ab86e2b6bc23054616bf6ac562013bf60af8cAffected 5bd8baab087dff657e05387aee802e70304cc813 to before 36519e3d941fc99d3b52c134dbaf311f987a4708Affected 5bd8baab087dff657e05387aee802e70304cc813 to before 322e48187e0245ab2fff6fec2220b0cae677dbecAffected 5bd8baab087dff657e05387aee802e70304cc813 to before b84091ceddc9f133229dceab3ccc930bf27f9cbaAffected 5bd8baab087dff657e05387aee802e70304cc813 to before c093468aea8277f77272a4f199b2e15e19cabb59Affected 5bd8baab087dff657e05387aee802e70304cc813 to before 65f3b3fc2347b89fe21db1e92c7681368415f095Affected 5bd8baab087dff657e05387aee802e70304cc813 to before dfa0d7b0ff1eb6b2c416b8fdb9b4f2cefba57a40Affected 2c66b0c95bb0aa7652ba1eba293d0d5993b35a38Affected ef6f83df1209a7d9bd1c605a62457d4c00f9179eAffected 3defefd22ad5fbbe639b6157fb7e6311b2bf333dAffected b657030870bb5351c5b1e84d4e9f186da6ca0496Affected 5.10.113 to before 5.10.259Affected 5.15.36 to before 5.15.210Affected 4.14.288 to before 4.15Affected 4.19.252 to before 4.20Affected 5.4.205 to before 5.5Affected 5.17.5 to before 5.18Affected
LinuxLinux	5.18Affected before 5.18Not affected 5.10.259 through 5.10.Not affected 5.15.210 through 5.15.Not affected 6.1.176 through 6.1.Not affected 6.6.143 through 6.6.Not affected 6.12.93 through 6.12.Not affected 6.18.35 through 6.18.Not affected 7.0.12 through 7.0.*Not affected 7.1 and laterNot affected

Product

Versions

LinuxLinux

c075c3ea031757f8ea2d34567565b61a868c08d5 to before 566295735530ee513326049b0540f32ec050bf2eAffected
a583f2f3c8788bffd7fd7baeb76bd6d80543d7ea to before 5d7ab86e2b6bc23054616bf6ac562013bf60af8cAffected
5bd8baab087dff657e05387aee802e70304cc813 to before 36519e3d941fc99d3b52c134dbaf311f987a4708Affected
5bd8baab087dff657e05387aee802e70304cc813 to before 322e48187e0245ab2fff6fec2220b0cae677dbecAffected
5bd8baab087dff657e05387aee802e70304cc813 to before b84091ceddc9f133229dceab3ccc930bf27f9cbaAffected
5bd8baab087dff657e05387aee802e70304cc813 to before c093468aea8277f77272a4f199b2e15e19cabb59Affected
5bd8baab087dff657e05387aee802e70304cc813 to before 65f3b3fc2347b89fe21db1e92c7681368415f095Affected
5bd8baab087dff657e05387aee802e70304cc813 to before dfa0d7b0ff1eb6b2c416b8fdb9b4f2cefba57a40Affected
2c66b0c95bb0aa7652ba1eba293d0d5993b35a38Affected
ef6f83df1209a7d9bd1c605a62457d4c00f9179eAffected
3defefd22ad5fbbe639b6157fb7e6311b2bf333dAffected
b657030870bb5351c5b1e84d4e9f186da6ca0496Affected
5.10.113 to before 5.10.259Affected
5.15.36 to before 5.15.210Affected
4.14.288 to before 4.15Affected
4.19.252 to before 4.20Affected
5.4.205 to before 5.5Affected
5.17.5 to before 5.18Affected

LinuxLinux

5.18Affected
before 5.18Not affected
5.10.259 through 5.10.*Not affected
5.15.210 through 5.15.*Not affected
6.1.176 through 6.1.*Not affected
6.6.143 through 6.6.*Not affected
6.12.93 through 6.12.*Not affected
6.18.35 through 6.18.*Not affected
7.0.12 through 7.0.*Not affected
7.1 and laterNot affected

References

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