CVE-2024-56657 ALSA: control: Avoid WARN() for symlink errors
A Linux kernel ALSA control issue caused excessive warnings on symlink errors, potentially confusing fuzzers and leading to 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-2024-56657?
CVE-2024-56657 is a medium-severity denial of service vulnerability in Linux kernel, published on 27 Dec 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:
ALSA: control: Avoid WARN() for symlink errors
Using WARN() for showing the error of symlink creations don't give more information than telling that something goes wrong, since the usual code path is a lregister callback from each control element creation. More badly, the use of WARN() rather confuses fuzzer as if it were serious issues.
This patch downgrades the warning messages to use the normal dev_err() instead of WARN(). For making it clearer, add the function name to the prefix, too.
Which versions are affected by CVE-2024-56657?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2024-56657?
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-2024-56657 being exploited?
There is no known exploitation of CVE-2024-56657 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-54804, AZL-54842, BELL-CVE-2024-56657, DEBIAN-CVE-2024-56657, GHSA-xpv3-x3xh-h28r, ROOT-OS-DEBIAN-12-CVE-2024-56657 and 2 more.