fuse: reject oversized dirents in page cache (Linux Linux)

CVE-2026-31694
HIGH 7.8

En bref

Source
NVD
EPSS
EPSS 0.28 % · centile 21 ()
État
PUBLISHED
Publiée
Mise à jour
Attribuée par
Linux
Statut NVD
Analyzed

Description

In the Linux kernel, the following vulnerability has been resolved: fuse: reject oversized dirents in page cache fuse_add_dirent_to_cache() computes a serialized dirent size from the server-controlled namelen field and copies the dirent into a single page-cache page. The existing logic only checks whether the dirent fits in the remaining space of the current page and advances to a fresh page if not. It never checks whether the dirent itself exceeds PAGE_SIZE. As a result, a malicious FUSE server can return a dirent with namelen=4095, producing a serialized record size of 4120 bytes. On 4 KiB page systems this causes memcpy() to overflow the cache page by 24 bytes into the following kernel page. Reject dirents that cannot fit in a single page before copying them into the readdir cache.

Références

Scores

VersionScoreVecteurÉvalué par
CVSS 3.1HIGH 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HLinux
CVSS 3.1HIGH 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HNVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary)

Références européennes

Avis du CERT-FR

Configurations affectées (CPE NVD)

Produits affectés

ProduitVersions
Linux · Linuxaffected 27992ef80770d61a57f6c3a551735b08cefdffa3 < 7de93abfaae1b2dc94da8a07a36421bd073f1d8f ; affected 27992ef80770d61a57f6c3a551735b08cefdffa3 < 474ce83c96a55f2eeb14dee2be375eeadfdacdf5 ; affected 27992ef80770d61a57f6c3a551735b08cefdffa3 < 51a8de6c50bf947c8f534cd73da4c8f0a13e7bed
Linux · Linuxaffected 6.15 ; unaffected 0 < 6.15 ; unaffected 6.18.25 ≤ 6.18.* ; unaffected 7.0.2 ≤ 7.0.* ; unaffected 7.1 ≤ *

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