🛡️ CVE-2025-37858 — debian-linux

🟡 CVSS 5.5 — Medium ✅ No Known Exploit CWE-190 NVD
5.5
CVSS Score
0 Low4 Medium7 High9 Critical10

Description

fs/jfs: Prevent integer overflow in AG size calculation

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

fs/jfs: Prevent integer overflow in AG size calculation

The JFS filesystem calculates allocation group (AG) size using 1 <<

l2agsize in dbExtendFS(). When l2agsize exceeds 31 (possible with >2TB

aggregates on 32-bit systems), this 32-bit shift operation causes undefined

behavior and improper AG sizing.

On 32-bit architectures:

  • Left-shifting 1 by 32+ bits results in 0 due to integer overflow
  • This creates invalid AG sizes (0 or garbage values) in

sbi->bmap->db_agsize

  • Subsequent block allocations would reference invalid AG structures
  • Could lead to:
  • Filesystem corruption during extend operations
  • Kernel crashes due to invalid memory accesses
  • Security vulnerabilities via malformed on-disk structures

Fix by casting to s64 before shifting:

bmp->db_agsize = (s64)1 << l2agsize;

This ensures 64-bit arithmetic even on 32-bit architectures. The cast

matches the data type of db_agsize (s64) and follows similar patterns in

JFS block calculation code.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

How this vulnerability can be exploited

This issue can be reached with local access to the system, attack complexity is low, an attacker needs low-level privileges on the target. No user interaction is required. The scope is unchanged, so the impact stays within the vulnerable component. Rated impact: confidentiality none, integrity none, availability high.

Weakness class

CVE-2025-37858 is classified as CWE-190: Integer Overflow or Wraparound. Arithmetic produces a value too large for its type and wraps around, so a later size or bounds check passes when it should not.

Affected software

CVE-2025-37858 is recorded against 3 packages.

  • debian-linux
  • kernel (from 6.14.0 up to 6.14.3)
  • linux-kernel (from 6.14 up to 6.14.3)

Timeline and source

Published on 9 May 2025 and last revised on 17 June 2026. No public exploit is currently recorded for this entry. A vendor advisory or fix has been published. Record sourced from NVD.

References

git.kernel.org
git.kernel.org
git.kernel.org
git.kernel.org
git.kernel.org
git.kernel.org
git.kernel.org
git.kernel.org
git.kernel.org
lists.debian.org
lists.debian.org

CVE-2025-37858 on other distributions

Each distribution ships its own build and its own fixed version. Pick the one you run:

Details

Severity MEDIUM
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
CWE CWE-190
Public Exploit ✅ No
Source NVD
Published 2025-05-09
Updated 2026-08-12
Modified 2026-06-17

Affected Packages

Software From version Fixed in
debian-linux — —
kernel 6.14.0 6.14.3
linux-kernel 6.14 6.14.3

References

Similar Threats

Vulnerability Monitoring

Track new vulnerabilities in debian-linux

CVE-2025-37858 is rated CVSS 5.5 Medium. BotEraser monitors your WordPress installation and notifies you when software you use appears in our vulnerability database.

Set Up Free Alerts →

No credit card required  ·  Results in minutes

ⓘ Data Notice: The information presented above has been compiled from publicly available internet sources. Boteraser aggregates this data solely for informational purposes and does not independently classify, evaluate, or endorse any findings about the vulnerabilities listed. The accuracy and completeness of this information is the sole responsibility of the original publishers. Boteraser and its operators accept no liability for any decisions made based on this data.