CVE-2026-90427 iommu/tegra241-cmdqv: Don't fall back to a freed smmu after devm_krealloc()
A use-after-free vulnerability in the Linux kernel's Tegra241 CMDQV driver allows attackers to cause denial of service or execute arbitrary code.
- 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-2026-90427?
CVE-2026-90427 is a high-severity use after free 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:
iommu/tegra241-cmdqv: Don't fall back to a freed smmu after devm_krealloc()
__tegra241_cmdqv_probe() uses devm_krealloc() to grow @smmu into the larger tegra241_cmdqv, which frees the original @smmu once it relocates. A failure after that returned NULL, and the caller then dereferenced the freed @smmu on its fallback path.
Return an int and take @smmu by reference instead, then update *smmu to the reallocated pointer after devm_krealloc() succeeds, so the caller and its fallback path both use the live @smmu rather than the freed original.
Which versions are affected by CVE-2026-90427?
How do I fix CVE-2026-90427?
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-2026-90427 being exploited?
There is no known exploitation of CVE-2026-90427 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-90427, DEBIAN-CVE-2026-90427, GHSA-7wgr-jrpm-fgrv, UBUNTU-CVE-2026-90427.