7.8

CVE-2025-40190: linux

CVSS: 7.8v3.1HighDeferred
AliasesUBUNTU-CVE-2025-40190DEBIAN-CVE-2025-40190
Published 12-11-2025Last modified 05-08-2026
Open JSON

Vulnerability summary

CVE-2025-40190 is a high (CVSS 7.8) vulnerability in linux. EPSS estimates a 0.18% chance of exploitation in the next 30 days, higher than 6.9% of scored vulnerabilities.

Overall risk
31/100
0100
Medium · default modelHow is this calculated?
CVSS score
7.8/10
010
High · v3.1 (CVE.org)
EPSS score
0.18%
0%100%
Low · +0.01 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 14 · Related 12
DLA-4379-1DLA-4404-1OPENSUSE-SU-2026:20145-1SUSE-SU-2026:0278-1SUSE-SU-2026:0281-1SUSE-SU-2026:0315-1

Timeline

  1. 12-11-2025
    PublishedVulnerability first disclosed.
  2. 05-08-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: ext4: guard against EA inode refcount underflow in xattr update syzkaller found a path where ext4_xattr_inode_update_ref() reads an EA inode refcount that is already <= 0 and then applies ref_change (often -1). That lets the refcount underflow and we proceed with a bogus value, triggering errors like: EXT4-fs error: EA inode <n> ref underflow: ref_count=-1 ref_change=-1 EXT4-fs warning: ea_inode dec ref err=-117 Make the invariant explicit: if the current refcount is non-positive, treat this as on-disk corruption, emit ext4_error_inode(), and fail the operation with -EFSCORRUPTED instead of updating the refcount. Delete the WARN_ONCE() as negative refcounts are now impossible; keep error reporting in ext4_error_inode(). This prevents the underflow and the follow-on orphan/cleanup churn.

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.18%

Chance of exploitation in the next 30 days

Percentile

7%

Versus all other CVEs

30-day change

+0.01 pp

From 0.17% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.18%

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

Ubuntu169 products
  • linuxAll versions (No fix recorded)
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded)
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian1 product
  • linux< 6.1.158-1 | < 6.12.57-1 | < 6.17.6-1
Linux1 product
  • linux≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < ea39e712c2f5ae148ee5515798ae03523673e002 | ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 1cfb3e4ddbdc8e02e637b8852540bd4718bf4814 | ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 505e69f76ac497e788f4ea0267826ec7266b40c8 | ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 3d6269028246f4484bfed403c947a114bb583631 | ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 79ea7f3e11effe1bd9e753172981d9029133a278 | ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 6b879c4c6bbaab03c0ad2a983953bd1410bb165e | ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 440b003f449a4ff2a00b08c8eab9ba5cd28f3943 | ≥ 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2, < 57295e835408d8d425bef58da5253465db3d6888 | < 5.4.301 | < 5.10.246 | < 5.15.195 | < 6.1.157 | < 6.6.113 | < 6.12.54 | < 6.17.4

3 vendors · 171 products

References

13 links
Show all 13 references