CVE-2025-39823Improper Validation of Array Index in Linux

Severity
7.8HIGHNVD
EPSS
0.0%
top 95.83%
CISA KEV
Not in KEV
Exploit
No known exploits
Timeline
PublishedSep 16
Latest updateApr 9

Description

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 vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitability: 1.8 | Impact: 5.9

Affected Packages3 packages

NVDlinux/linux_kernel4.195.4.298+7
Debianlinux/linux_kernel< 5.10.244-1+3
CVEListV5linux/linux4180bf1b655a791a0a6ef93a2ffffc762722c78272777fc31aa7ab2ce00f44bfa3929c6eabbeaf48+8

Also affects: Debian Linux 11.0

Patches

🔴Vulnerability Details

3
CVEList
KVM: x86: use array_index_nospec with indices that come from guest2025-09-16
GHSA
GHSA-g6f5-85j8-c4fr: 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_2025-09-16
OSV
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_id2025-09-16

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CVE-2025-39823 — Improper Validation of Array Index | cvebase