CVE-2026-74358 ext4: fix fast commit wait/wake bit mapping on 64-bit
A race condition in the Linux kernel ext4 fast commit path can cause system hangs or crashes due to incorrect wait/wake bit mapping on 64-bit systems.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-74358?
CVE-2026-74358 is a vulnerability in Linux, published on 15 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
ext4: fix fast commit wait/wake bit mapping on 64-bit
On 64-bit, ext4 dynamic inode states live in the upper half of i_flags, and ext4_test_inode_state() applies the corresponding +32 offset.
The fast-commit wait and wake paths open-coded the wait key with the raw EXT4_STATE_* value. Add small helpers for the state wait word and bit, and use them for the FC_COMMITTING and FC_FLUSHING_DATA waits so the wait key follows the same mapping as the state helpers.
Which versions are affected by CVE-2026-74358?
How do I fix CVE-2026-74358?
Apply the vendor's patch.
Is CVE-2026-74358 being exploited?
There is no known exploitation of CVE-2026-74358 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-74358, DEBIAN-CVE-2026-74358, GHSA-pvr9-cffv-xgvv, UBUNTU-CVE-2026-74358.