CVE-2026-31694
highIn the Linux kernel, the following vulnerability has been resolved: fuse: reject oversized dirents in page cache fuse_add_dirent_to_cache() computes a serial…
Vendor / product: Linux — linux kernel
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:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Affected products
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
References
- https://git.kernel.org/stable/c/474ce83c96a55f2eeb14dee2be375eeadfdacdf5 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://git.kernel.org/stable/c/51a8de6c50bf947c8f534cd73da4c8f0a13e7bed 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://git.kernel.org/stable/c/7de93abfaae1b2dc94da8a07a36421bd073f1d8f 416baaa9-dc9f-4396-8d5f-8c081fb06d67
- https://cert-portal.siemens.com/productcert/html/ssa-784472.html 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e

