CVE-2026-93083 firmware: arm_scmi: Unwind TX receiver mailbox setup failure
A resource leak in the Linux kernel SCMI driver can cause denial of service by leaving mailbox channels busy after setup failures.
- 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-2026-93083?
CVE-2026-93083 is a denial of service vulnerability in Linux, published on 17 Sep 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:
firmware: arm_scmi: Unwind TX receiver mailbox setup failure
mailbox_chan_setup() can request an additional unidirectional TX receiver channel after successfully acquiring the primary channel. If that second request fails, the function returns immediately and leaves the primary channel allocated.
Unwind the primary mailbox channel before returning the error so probe deferral or other setup failures do not leave the channel busy for later probe attempts.
Which versions are affected by CVE-2026-93083?
How do I fix CVE-2026-93083?
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-2026-93083 being exploited?
There is no known exploitation of CVE-2026-93083 in the wild and no public exploit code.
Sources
Also known as AZL-102300, BELL-CVE-2026-93083, DEBIAN-CVE-2026-93083, GHSA-fp4r-fj2q-pj98, UBUNTU-CVE-2026-93083.