CVE-2026-90205 ocfs2: validate orphan slot during inode read
A corrupted OCFS2 inode can cause an out-of-bounds memory access leading to a use-after-free, potentially allowing denial of service or code execution.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-90205?
CVE-2026-90205 is a high-severity use after free vulnerability in Linux, published on 17 Sep 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
In the Linux kernel, the following vulnerability has been resolved:
ocfs2: validate orphan slot during inode read
Patch series "ocfs2: validate active orphan slots during inode read".
OCFS2 trusts active ordinary and append-DIO orphan slots read from dinodes. A corrupted slot can therefore index osb_orphan_wipes or the slot-local system-inode cache outside their allocations before the corruption is reported.
Patch 1 validates the ordinary orphan slot used by inode wipe processing. Patch 2 validates the append-DIO orphan slot used by DIO completion and orphan recovery. Both checks reject corrupt metadata at the existing inode validation boundary.
This patch (of 2):
[BUG] A corrupted dinode with OCFS2_ORPHANED_FL can carry an i_orphaned_slot outside the mounted filesystem slot range. ocfs2_wipe_inode() uses it to index osb_orphan_wipes before looking up the orphan directory, causing an out-of-bounds memory access.
BUG: KASAN: slab-use-after-free in ocfs2_get_system_file_inode+0x780/0x820 fs/ocfs2/sysfile.c:102 Read of size 8 at addr ffff88800b767c00 by task kworker/u8:3/85 Call Trace: ... ocfs2_get_system_file_inode+0x780/0x820 fs/ocfs2/sysfile.c:102 ocfs2_wipe_inode+0x292/0xf70 fs/ocfs2/inode.c:840 ocfs2_delete_inode fs/ocfs2/inode.c:1155 [inline] ocfs2_evict_inode+0x6c9/0x1170 fs/ocfs2/inode.c:1295 evict+0x38e/0x8f0 fs/inode.c:810 iput_final fs/inode.c:1914 [inline] iput fs/inode.c:1966 [inline] iput+0x55b/0x8b0 fs/inode.c:1926 ocfs2_recover_orphans+0x610/0xe40 fs/ocfs2/journal.c:2374 ocfs2_complete_recovery+0x5af/0xd00 fs/ocfs2/journal.c:1373 ...
[CAUSE] ocfs2_validate_inode_block() validates i_suballoc_slot but leaves the active ordinary orphan slot unchecked. Downstream consumers assume that the value is smaller than osb->max_slots.
[FIX] Reject an active i_orphaned_slot outside the slot range during dinode validation, before the inode reaches orphan wipe processing.
Which versions are affected by CVE-2026-90205?
How do I fix CVE-2026-90205?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-90205 being exploited?
There is no known exploitation of CVE-2026-90205 in the wild and no public exploit code.
Sources
Also known as AZL-102285, BELL-CVE-2026-90205, DEBIAN-CVE-2026-90205, GHSA-hqp2-385x-jjhh, UBUNTU-CVE-2026-90205.