CVE-2026-46018 ALSA: usb-audio: stop parsing UAC2 rates at MAX_NR_RATES
A malformed USB audio device response causes the Linux kernel to loop indefinitely while holding a mutex, leading to a system hang or 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-2026-46018?
CVE-2026-46018 is a medium-severity denial of service vulnerability in Linux kernel, published on 27 May 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:
ALSA: usb-audio: stop parsing UAC2 rates at MAX_NR_RATES
parse_uac2_sample_rate_range() caps the number of enumerated rates at MAX_NR_RATES, but it only breaks out of the current rate loop. A malformed UAC2 RANGE response with additional triplets continues parsing the remaining triplets and repeatedly prints "invalid uac2 rates" while probe still holds register_mutex.
Stop the whole parse once the cap is reached and return the number of rates collected so far.
Which versions are affected by CVE-2026-46018?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-46018?
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-2026-46018 being exploited?
There is no known exploitation of CVE-2026-46018 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-88740, BELL-CVE-2026-46018, DEBIAN-CVE-2026-46018, GHSA-fgw2-9pf4-66rf, ROOT-OS-DEBIAN-11-CVE-2026-46018, ROOT-OS-DEBIAN-12-CVE-2026-46018 and 3 more.