CVE-2021-46923 fs/mount_setattr: always cleanup mount_kattr
A resource leak in the Linux kernel's mount_setattr function can lead to denial of service by failing to clean up references on error paths.
- 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-2021-46923?
CVE-2021-46923 is a medium-severity vulnerability in Linux kernel, published on 27 Feb 2024. 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:
fs/mount_setattr: always cleanup mount_kattr
Make sure that finish_mount_kattr() is called after mount_kattr was succesfully built in both the success and failure case to prevent leaking any references we took when we built it. We returned early if path lookup failed thereby risking to leak an additional reference we took when building mount_kattr when an idmapped mount was requested.
Weakness: CWE-668
Which versions are affected by CVE-2021-46923?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2021-46923?
Apply the vendor's patch.
Is CVE-2021-46923 being exploited?
There is no known exploitation of CVE-2021-46923 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2021-46923, GHSA-f93f-4q67-pcmr, UBUNTU-CVE-2021-46923.