CVE-2026-31671: linux
Vulnerability summary
CVE-2026-31671 is a medium (CVSS 5.5) vulnerability in linux. EPSS estimates a 0.17% chance of exploitation in the next 30 days, higher than 6.1% of scored vulnerabilities.
Advisory lineage
Upstream 0 · Downstream 41 · Related 39Timeline
- 24-04-2026PublishedVulnerability first disclosed.
- 15-10-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: xfrm_user: fix info leak in build_report() struct xfrm_user_report is a __u8 proto field followed by a struct xfrm_selector which means there is three "empty" bytes of padding, but the padding is never zeroed before copying to userspace. Fix that up by zeroing the structure before setting individual member variables.
CVSS metrics
3 scores · 3 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.17%
Chance of exploitation in the next 30 days
Percentile
6%
Versus all other CVEs
30-day change
+0.05 pp
From 0.12% on 21-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected 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≥ 97a64b4577ae2bc5599dbd008a3cd9e25de9b9f5, < d27c02eec529f78055a46a5c9e6c62684382b2d8 | ≥ 97a64b4577ae2bc5599dbd008a3cd9e25de9b9f5, < 716c546e88cfe49d841658240e10cb57bc50a2cc | ≥ 97a64b4577ae2bc5599dbd008a3cd9e25de9b9f5, < 0616314b3b34f24cbb91da8c6bd8bcdc4c8592f9 | ≥ 97a64b4577ae2bc5599dbd008a3cd9e25de9b9f5, < e0c8542c3d097ed4205ded51868195d5d6ddac62 | ≥ 97a64b4577ae2bc5599dbd008a3cd9e25de9b9f5, < ff5ee507302303b15859753c3e0d67d38fd12c88 | ≥ 97a64b4577ae2bc5599dbd008a3cd9e25de9b9f5, < 6c55714c931051cd7f4839c19ce0867179fd22fe | ≥ 97a64b4577ae2bc5599dbd008a3cd9e25de9b9f5, < 0a30dceb0e1f0c480d2482e6d7cebf8aebb6eb72 | ≥ 97a64b4577ae2bc5599dbd008a3cd9e25de9b9f5, < d10119968d0e1f2b669604baf2a8b5fdb72fa6b4 | 2.6.19
- linux_kernel≥ 2.6.19.1, < 5.10.253 | ≥ 5.11, < 5.15.203 | ≥ 5.16, < 6.1.169 | ≥ 6.2, < 6.6.135 | ≥ 6.7, < 6.12.82 | ≥ 6.13, < 6.18.23 | ≥ 6.19, < 6.19.13 | 2.6.19 | 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