CVE-2026-31694
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.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| sles | affected | | |
| debian | bookworm | affected | |
| debian | bullseye | affected | |
| debian | forky | fixed | 7.0.3-1 |
| debian | sid | fixed | 7.0.3-1 |
| debian | trixie | fixed | 6.12.85-1 |
| linux-kernel | affected | 6.6.136 | |
| linux-kernel | 7.1 | affected | |
| windows | affected | |
References
- https://git.kernel.org/stable/c/45c05af36311624c1148123caeb011312495d86b
- https://git.kernel.org/stable/c/474ce83c96a55f2eeb14dee2be375eeadfdacdf5
- https://git.kernel.org/stable/c/51a8de6c50bf947c8f534cd73da4c8f0a13e7bed
- https://git.kernel.org/stable/c/7de93abfaae1b2dc94da8a07a36421bd073f1d8f
- https://git.kernel.org/stable/c/d23ad78bfd205eac26766e38ba7d79f279131098
- https://www.suse.com/security/cve/CVE-2026-31694.html
- https://security-tracker.debian.org/tracker/CVE-2026-31694
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-31694
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.