CVE-2025-39823

In the Linux kernel, the following vulnerability has been resolved: KVM: x86: use array_index_nospec with indices that come from guest min and dest_id are guest-controlled indices. Using array_index_nospec() after the bounds checks clamps these values to mitigate speculative execution side-channels.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://git.kernel.org/stable/c/31a0ad2f60cb4816e06218b63e695eb72ce74974	Patch
https://git.kernel.org/stable/c/33e974c2d5a82b2f9d9ba0ad9cbaabc1c8e3985f	Patch
https://git.kernel.org/stable/c/67a05679621b7f721bdba37a5d18665d3aceb695	Patch
https://git.kernel.org/stable/c/72777fc31aa7ab2ce00f44bfa3929c6eabbeaf48	Patch
https://git.kernel.org/stable/c/c87bd4dd43a624109c3cc42d843138378a7f4548	Patch
https://git.kernel.org/stable/c/d51e381beed5e2f50f85f49f6c90e023754efa12	Patch
https://git.kernel.org/stable/c/f49161646e03d107ce81a99c6ca5da682fe5fb69	Patch
https://git.kernel.org/stable/c/f57a4bd8d6cb5af05b8ac1be9098e249034639fb	Patch
https://lists.debian.org/debian-lts-announce/2025/10/msg00007.html	Third Party Advisory Mailing List
https://lists.debian.org/debian-lts-announce/2025/10/msg00008.html	Third Party Advisory Mailing List

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel::::::::
	cpe:2.3:o:linux:linux_kernel:6.17:rc1::::::
	cpe:2.3:o:linux:linux_kernel:6.17:rc2::::::
	cpe:2.3:o:linux:linux_kernel:6.17:rc3::::::

Configuration 2 (hide)

cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

History

No history.

Information

Published : 2025-09-16 13:16

Updated : 2026-01-16 20:38

NVD link : CVE-2025-39823

Mitre link : CVE-2025-39823

CVE.ORG link : CVE-2025-39823

JSON object : View

Products Affected

debian

debian_linux

linux

linux_kernel

CWE

CWE-129

Improper Validation of Array Index

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