CVE-2026-31664

Updated on 24 Apr 2026

Severity

5.5 Medium severity

Details

CVSS score
5.5
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Overview

About vulnerability

In the Linux kernel, the following vulnerability has been resolved:

xfrm: clear trailing padding in build_polexpire()

build_expire() clears the trailing padding bytes of struct xfrm_user_expire after setting the hard field via memset_after(), but the analogous function build_polexpire() does not do this for struct xfrm_user_polexpire.

The padding bytes after the __u8 hard field are left uninitialized from the heap allocation, and are then sent to userspace via netlink multicast to XFRMNLGRP_EXPIRE listeners, leaking kernel heap memory contents.

Add the missing memset_after() call, matching build_expire().

Details

Fixes

KernelCare state

Live-patch status from KernelCare for each operating system.

Operating system Status Covered kernels
AlmaLinux 9.2 ESU Released
17 kernels
  • 5.14.0-284.1101.el9_2.tuxcare.7.els20
  • 5.14.0-284.1101.el9_2.tuxcare.7.els21
  • 5.14.0-284.1101.el9_2.tuxcare.7.els23
  • 5.14.0-284.1101.el9_2.tuxcare.7.els22
  • 5.14.0-284.1101.el9_2.tuxcare.7.els14
  • 5.14.0-284.1101.el9_2.tuxcare.7.els18
  • 5.14.0-284.1101.el9_2.tuxcare.7.els16
  • 5.14.0-284.1101.el9_2.tuxcare.7.els15
  • 5.14.0-284.1101.el9_2.tuxcare.7.els17
  • 5.14.0-284.1101.el9_2.tuxcare.7.els19
  • 5.14.0-284.1101.el9_2.tuxcare.7.els24
  • 5.14.0-284.1101.el9_2.tuxcare.7.els25
  • 5.14.0-284.1101.el9_2.tuxcare.7.els26
  • 5.14.0-284.1101.el9_2.tuxcare.7.els27
  • 5.14.0-284.1101.el9_2.tuxcare.7.els28
  • 5.14.0-284.1101.el9_2.tuxcare.7.els29
  • 5.14.0-284.1101.el9_2.tuxcare.7.els30
AlmaLinux 9.6 ESU Released
11 kernels
  • 5.14.0-570.62.1.el9_6.tuxcare.1.els1
  • 5.14.0-570.62.1.el9_6.tuxcare.1.els2
  • 5.14.0-570.62.1.el9_6.tuxcare.1.els3
  • 5.14.0-570.62.1.el9_6.tuxcare.1.els4
  • 5.14.0-570.62.1.el9_6.tuxcare.1.els5
  • 5.14.0-570.62.1.el9_6.tuxcare.1.els6
  • 5.14.0-570.62.1.el9_6.tuxcare.1.els7
  • 5.14.0-570.62.1.el9_6.tuxcare.5.els1
  • 5.14.0-570.62.1.el9_6.tuxcare.5.els2
  • 5.14.0-570.62.1.el9_6.tuxcare.5.els3
  • 5.14.0-570.62.1.el9_6.tuxcare.5.els4
Amazon Linux 2023 Planned
Debian 11 Planned
Debian 11 cloud Planned
Debian 12 Planned
Debian 13 Planned
Ubuntu 22.04 Planned
Ubuntu 24.04 Planned