CVE-2026-31694

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.

Affected products

Linux Kernel

Linux Linux Kernel

< 6.6.136, 6.12.84, 6.18.25, 7.0.2, 7.1

Fix

Available

CVSS 3.1

7.8 HIGH

EPSS

0.3% (21th percentile)

NVD status

Modified

Published

2026-05-01