High severity · published May 1, 2026
CVE-2026-31694
fuse: reject oversized dirents in page cache
7.8
CVSS
0.3%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 21% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
KE
Kernel · Linux
6.15 before 6.18.25; 6.19 before 7.0.2; 7.1; 7.1 · source: NVD
LI
Linux · Linux
27992ef80770d61a57f6c3a551735b08cefdffa3 before 7de93abfaae1b2dc94da8a07a36421bd073f1d8f; 27992ef80770d61a57f6c3a551735b08cefdffa3 before 474ce83c96a55f2eeb14dee2be375eeadfdacdf5; 27992ef80770d61a57f6c3a551735b08cefdffa3 before 51a8de6c50bf947c8f534cd73da4c8f0a13e7bed; 6.15 · source: vendor
SS
Simatic S7-1500 TM Mfp Firmware · Siemens
All versions, or not specified · source: NVD