fat: avoid parent link count underflow in rmdir (Linux Linux)

CVE-2026-45915
MEDIUM 5.5

At a glance

Source
NVD
EPSS
EPSS 0.16 % · percentile 5 ()
State
PUBLISHED
Published
Updated
Assigner
Linux
NVD status
Undergoing Analysis

Description

In the Linux kernel, the following vulnerability has been resolved: fat: avoid parent link count underflow in rmdir Corrupted FAT images can leave a directory inode with an incorrect i_nlink (e.g. 2 even though subdirectories exist). rmdir then unconditionally calls drop_nlink(dir) and can drive i_nlink to 0, triggering the WARN_ON in drop_nlink(). Add a sanity check in vfat_rmdir() and msdos_rmdir(): only drop the parent link count when it is at least 3, otherwise report a filesystem error.

References

Scores

VersionScoreVectorScored by
CVSS 3.1MEDIUM 5.5CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:HNVD · nvd@nist.gov (Primary)

European references

CERT-FR advisories

Affected configurations (NVD CPE)

Affected products

ProductVersions
Linux · Linuxaffected 9a53c3a783c2fa9b969628e65695c11c3e51e673 < 7fe0de287e931e07cb96ecf1f449b2ebdb0e1115 ; affected 9a53c3a783c2fa9b969628e65695c11c3e51e673 < 9894c79fd9466612d0514be157b5c30cd93aa645 ; affected 9a53c3a783c2fa9b969628e65695c11c3e51e673 < cd569b87378b9c33ae13c23d6bb9d205d66f7c4b ; affected 9a53c3a783c2fa9b969628e65695c11c3e51e673 < d3b7ffa90f613938128432c7b2f35b7aa4bdd86b ; affected 9a53c3a783c2fa9b969628e65695c11c3e51e673 < 955c5d670b5ae07c78f4345e23a895638db96ce1 ; affected 9a53c3a783c2fa9b969628e65695c11c3e51e673 < 17866f8a0822d414cb02e621cf003a7d04396ef8
Linux · Linuxaffected 2.6.19 ; unaffected 0 < 2.6.19 ; unaffected 5.10.252 ≤ 5.10.* ; unaffected 5.15.202 ≤ 5.15.* ; unaffected 6.1.165 ≤ 6.1.* ; unaffected 6.6.128 ≤ 6.6.*

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD