CVE-2025-39815: Linux Kernel

Medium severity, CVSS 5.5. EPSS: 0.2% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: RISC-V: KVM: fix stack overrun when loading vlenb The userspace load can put up to 2048 bits into an xlen bit stack buffer. We want only xlen bits, so check the size beforehand.

Affected products

• Linux Linux Kernel: from 6.8, before 6.12.45 (fixed in 6.12.45); from 6.13, before 6.16.5 (fixed in 6.16.5); version 6.17 only

Published 2025-09-16. Last modified 2026-07-30.