5.5

CVE-2026-31664: linux

CVSS: 5.5v3.1MediumModified
AliasesUBUNTU-CVE-2026-31664DEBIAN-CVE-2026-31664
Published 24-04-2026Last modified 15-10-2026
Open JSON

Vulnerability summary

CVE-2026-31664 is a medium (CVSS 5.5) vulnerability in linux. EPSS estimates a 0.12% chance of exploitation in the next 30 days, higher than 1.7% of scored vulnerabilities.

Overall risk
22/100
0100
Low · default modelHow is this calculated?
CVSS score
5.5/10
010
Medium · v3.1 (NVD)
EPSS score
0.12%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 41 · Related 39
MGASA-2026-0108MGASA-2026-0110OPENSUSE-SU-2026:21388-1SUSE-SU-2026:22433-1SUSE-SU-2026:22436-1SUSE-SU-2026:22458-1

Timeline

  1. 24-04-2026
    PublishedVulnerability first disclosed.
  2. 15-10-2026
    Last modifiedVulnerability information updated.

Description

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().

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.12%

Chance of exploitation in the next 30 days

Percentile

2%

Versus all other CVEs

30-day change

0.00 pp

From 0.12% on 21-09-2026

21-09-202621-10-2026
EPSS score
0.12%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

No weakness data has been published for this record.

Affected systems

Ubuntu157 products
  • linuxAll versions (No fix recorded) | < 5.15.0-186.196 | < 6.8.0-136.136
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 5.15.0-1112.119 | < 6.8.0-1061.64
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < a5127501c8d30b5728791b1e340284ca5c9cc4bd | ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < e6f4ffe8596947a595c9544e73a73adcb0568b88 | ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < ac6985903db047eaff54db929e4bf6b06782788e | ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < c221ed63a2769a0af8bd849dfe25740048f34ef4 | ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < eda30846ea54f8ed218468e5480c8305ca645e37 | ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < b1dfd6b27df35ef4f87825aa5f607378d23ff0f2 | ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < e1af65c669ebb1666c54576614c01a7f9ffcfff6 | ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 71a98248c63c535eaa4d4c22f099b68d902006d0 | 2.6.12
  • linux_kernel≥ 2.6.12.1, < 6.1.169 | ≥ 6.2, < 6.6.135 | ≥ 6.7, < 6.12.82 | ≥ 6.13, < 6.18.23 | ≥ 6.19, < 6.19.13 | 2.6.12 | 2.6.12:rc2 | 2.6.12:rc3 | 2.6.12:rc4 | 2.6.12:rc5 | 7.0:rc1 | 7.0:rc2 | 7.0:rc3 | 7.0:rc4 | 7.0:rc5 | 7.0:rc6 | 7.0:rc7
Debian1 product
  • linux< 6.1.170-1 | < 6.12.85-1 | < 6.19.13-1

3 vendors · 160 products

References

43 links
Show all 43 references