CVE-2025-38701 ext4: do not BUG when INLINE_DATA_FL lacks system.data xattr
A maliciously crafted filesystem image can trigger a kernel BUG_ON crash in ext4, causing a denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-38701?
CVE-2025-38701 is a medium-severity denial of service vulnerability in Debian Debian Linux, published on 4 Sep 2025. 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: do not BUG when INLINE_DATA_FL lacks system.data xattr
A syzbot fuzzed image triggered a BUG_ON in ext4_update_inline_data() when an inode had the INLINE_DATA_FL flag set but was missing the system.data extended attribute.
Since this can happen due to a maiciouly fuzzed file system, we shouldn't BUG, but rather, report it as a corrupted file system.
Add similar replacements of BUG_ON with EXT4_ERROR_INODE() ii ext4_create_inline_data() and ext4_inline_data_truncate().
Weakness: CWE-617
Which versions are affected by CVE-2025-38701?
It affects 2 products.
Products include Debian Debian Linux, Linux kernel.
How do I fix CVE-2025-38701?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2025-38701 being exploited?
There is no known exploitation of CVE-2025-38701 in the wild and no public exploit code.
Other vulnerabilities in Debian Debian Linux
Sources
Also known as AZL-66899, AZL-73881, BELL-CVE-2025-38701, DEBIAN-CVE-2025-38701, GHSA-x687-v76r-f9gw, ROOT-OS-DEBIAN-11-CVE-2025-38701 and 4 more.