CVE-2026-53294 mailbox: mailbox-test: don't free the reused channel
A double-free vulnerability in the Linux kernel mailbox-test driver allows attackers to cause denial of service or potentially execute code.
- 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-2026-53294?
CVE-2026-53294 is a high-severity use after free vulnerability in Linux kernel, published on 26 Jun 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:
mailbox: mailbox-test: don't free the reused channel
The RX channel can be aliased to the TX channel if it has a different MMIO. This special case needs to be handled when freeing the channels otherwise a double-free occurs.
Weakness: CWE-415
Which versions are affected by CVE-2026-53294?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-53294?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2026-53294 being exploited?
There is no known exploitation of CVE-2026-53294 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2026-53294, DEBIAN-CVE-2026-53294, GHSA-grhq-rqc2-rhjr, ROOT-OS-DEBIAN-11-CVE-2026-53294, ROOT-OS-DEBIAN-12-CVE-2026-53294, ROOT-OS-UBUNTU-2204-CVE-2026-53294 and 2 more.