CVE-2026-64592 riscv: mm: Unconditionally sfence.vma for spurious fault
A missing TLB flush in the RISC-V Linux kernel can cause a crash during rare spurious faults, leading to local denial of service.
- 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-2026-64592?
CVE-2026-64592 is a denial of service vulnerability in Linux, published on 6 Aug 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:
riscv: mm: Unconditionally sfence.vma for spurious fault
Svvptc does not guarantee that it's safe to just return here. Since we have already cleared our bit, if, theoretically, the bounded timeframe for the accessed page to become valid still hasn't happened after sret, we could fault again and actually crash.
Hopefully, these spurious faults should be rare enough that this is an acceptable slowdown.
Which versions are affected by CVE-2026-64592?
How do I fix CVE-2026-64592?
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-2026-64592 being exploited?
There is no known exploitation of CVE-2026-64592 in the wild and no public exploit code.
Sources
Also known as BELL-CVE-2026-64592, DEBIAN-CVE-2026-64592, GHSA-m6hv-9h66-mmjv, UBUNTU-CVE-2026-64592.