CVE-2025-39823: KVM: x86: use array_index_nospec with indices that come from guest
In the Linux kernel, the following vulnerability has been resolved:
KVM: x86: use arrayindexnospec with indices that come from guest
min and destid are guest-controlled indices. Using arrayindexnospec() after the bounds checks clamps these values to mitigate speculative execution side-channels.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
debian/linuxto a version that resolves this vulnerability.Fixed in 6.1.176-1Fixed in 6.1.190-1Fixed in 6.12.107-1Fixed in 6.12.113-1Fixed in 7.2.12-1Fixed in 7.2.13-1
Event History
Frequently Asked Questions
What is the severity of CVE-2025-39823?
CVE-2025-39823 is classified as a medium severity vulnerability in the Linux kernel.
How do I fix CVE-2025-39823?
To fix CVE-2025-39823, update your Linux kernel to the latest version that includes the fix.
What platforms are affected by CVE-2025-39823?
CVE-2025-39823 affects all versions of the Linux kernel that are vulnerable to the issue related to KVM and guest-controlled indices.
What is the impact of CVE-2025-39823 on system security?
CVE-2025-39823 allows an attacker to potentially exploit guest-controlled indices, which may lead to information disclosure or system compromise.
Who is responsible for patching CVE-2025-39823?
The responsibility for patching CVE-2025-39823 falls on system administrators and users running affected versions of the Linux kernel.