CVE-2025-39815

RISC-V: KVM: fix stack overrun when loading vlenb

State: Published
Severity: 7.8 High
Published: Sep 16, 2025
Updated: Aug 5, 2026
Reserved: Apr 16, 2025

Description

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.

Scores

CVSS	Score	Vector	Source
3.1	7.8 High	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H	Linux
3.1	5.5 Medium	CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H	CISA-ADP

Weaknesses

The record names no weakness.

Affected Products

Product	Versions
LinuxLinux	2fa290372dfe7dd248b1c16f943f273a3e674f22 to before c76bf8359188a11f8fd790e5bbd6077894a245ccAffected 2fa290372dfe7dd248b1c16f943f273a3e674f22 to before 6d28659b692a0212f360f8bd8a58712b339f9aacAffected 2fa290372dfe7dd248b1c16f943f273a3e674f22 to before 799766208f09f95677a9ab111b93872d414fbad7Affected
LinuxLinux	6.8Affected before 6.8Not affected 6.12.45 through 6.12.Not affected 6.16.5 through 6.16.Not affected 6.17 and laterNot affected

References

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