CVE-2026-64082
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.13%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.13% probability · 3th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-908
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/0599aa23734c48de9bce36d043a9ec90c23945a1Patch
- https://git.kernel.org/stable/c/2a7d1daf2674fe7d5b1cc99a4e3b5f0f72d5958fPatch
- https://git.kernel.org/stable/c/66dedb6028c3df6c6a3372dd935b823917e150d5Patch
- https://git.kernel.org/stable/c/6ebcbb53fc9bc30843054ed99fd60b8e542628f4Patch
- https://git.kernel.org/stable/c/9e020156833f1ad0d425a1e3d85b65639f1c1c50Patch
- https://git.kernel.org/stable/c/f2d88b0d7aebfa4643fc58bbae57210c6daff9c6Patch
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.