CVE-2026-63912

Updated on 19 Jul 2026

Severity

9.8 Critical severity

Details

CVSS score
9.8

Overview

About vulnerability

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.

Details

KernelCare state

Live-patch status from KernelCare for each operating system.

Operating system Status Covered kernels
Amazon Linux 2023 Planned
Debian 12 Planned