CVE-2025-40049: linux

CVSS: UnknownDeferred
AliasesUBUNTU-CVE-2025-40049DEBIAN-CVE-2025-40049
Published 28-10-2025Last modified 11-05-2026
Open JSON

Vulnerability summary

CVE-2025-40049 is a vulnerability in linux with no CVSS score yet. EPSS estimates a 0.23% chance of exploitation in the next 30 days, higher than 12.5% of scored vulnerabilities.

Overall risk
0/100
0100
Minimal · default modelHow is this calculated?
CVSS score
Not scored
010
No CVSS score recorded
EPSS score
0.23%
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 52 · Related 47
DLA-4379-1DLA-4404-1DSA-6053-1MGASA-2025-0309MGASA-2025-0310OPENSUSE-SU-2025:15702-1

Timeline

  1. 28-10-2025
    PublishedVulnerability first disclosed.
  2. 11-05-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: Squashfs: fix uninit-value in squashfs_get_parent Syzkaller reports a "KMSAN: uninit-value in squashfs_get_parent" bug. This is caused by open_by_handle_at() being called with a file handle containing an invalid parent inode number. In particular the inode number is that of a symbolic link, rather than a directory. Squashfs_get_parent() gets called with that symbolic link inode, and accesses the parent member field. unsigned int parent_ino = squashfs_i(inode)->parent; Because non-directory inodes in Squashfs do not have a parent value, this is uninitialised, and this causes an uninitialised value access. The fix is to initialise parent with the invalid inode 0, which will cause an EINVAL error to be returned. Regular inodes used to share the parent field with the block_list_start field. This is removed in this commit to enable the parent field to contain the invalid inode number 0.

CVSS metrics

Risk metrics not yet published.

EPSS trend

Probability

0.23%

Chance of exploitation in the next 30 days

Percentile

13%

Versus all other CVEs

30-day change

+0.01 pp

From 0.21% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.23%

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

Ubuntu153 products
  • linuxAll versions (No fix recorded) | < 5.15.0-170.180 | < 6.8.0-106.106 | < 6.17.0-14.14
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 5.15.0-1100.107 | < 6.8.0-1050.53 | < 6.17.0-1007.7
  • 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≥ 122601408d20c77704268f1dea9f9ce4abf997c2, < f81a5bc9e924ee1950e0dd82bd10749048390f6e | ≥ 122601408d20c77704268f1dea9f9ce4abf997c2, < 382a47fae449e554ef1e8c198667fd2f3270b945 | ≥ 122601408d20c77704268f1dea9f9ce4abf997c2, < 61d38b5ce2782bff3cacaacbb8164087a73ed1a5 | ≥ 122601408d20c77704268f1dea9f9ce4abf997c2, < 81a2bca52d43fc9d9abf07408b91255131c5dc53 | ≥ 122601408d20c77704268f1dea9f9ce4abf997c2, < c28b0ca029edf5d0558abcd76cb8c732706cd339 | ≥ 122601408d20c77704268f1dea9f9ce4abf997c2, < 1b3ccd0019132880c94bb00ca7088c1749308f82 | ≥ 122601408d20c77704268f1dea9f9ce4abf997c2, < 91b99db7a92e57ff48a96a1b10fddfd2547e7f53 | ≥ 122601408d20c77704268f1dea9f9ce4abf997c2, < 74058c0a9fc8b2b4d5f4a0ef7ee2cfa66a9e49cf | 2.6.29

3 vendors · 155 products

References

42 links
Show all 42 references