CVE-2026-64082 riscv: Fix register corruption from uninitialized cregs on error
An attacker can exploit uninitialized stack data in the Linux kernel to leak kernel memory or corrupt register state, potentially leading to privilege escalation.
- 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-2026-64082?
CVE-2026-64082 is a high-severity vulnerability in Linux kernel, published on 19 Jul 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: Fix register corruption from uninitialized cregs on error
compat_riscv_gpr_set() calls cregs_to_regs() unconditionally, even when user_regset_copyin() fails. Since cregs is an uninitialized stack variable, a copyin failure causes uninitialized stack data to be written into the target task's pt_regs, corrupting its register state and potentially leaking kernel stack contents.
compat_restore_sigcontext() has the same issue: it calls cregs_to_regs() even when __copy_from_user() fails, leading to the same corruption of the signal-returning task's register state on error.
Only call cregs_to_regs() when the user copy succeeds.
Weakness: CWE-908
Which versions are affected by CVE-2026-64082?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2026-64082?
Apply the vendor's patch.
Is CVE-2026-64082 being exploited?
There is no known exploitation of CVE-2026-64082 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-92829, BELL-CVE-2026-64082, DEBIAN-CVE-2026-64082, GHSA-87cj-725f-6hr5, ROOT-OS-DEBIAN-12-CVE-2026-64082, ROOT-OS-DEBIAN-13-CVE-2026-64082 and 1 more.