CVE-2025-39823

CVE-2025-39823: vulnerability in Linux

KVM: x86: use array_index_nospec with indices that come from guest

Published · Updated

3Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackepss 0.2%
exploitation probability
0.2%top 93% of all CVEs
observed exploitation
nono source reports it
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.
Affected products
Linux · Linux
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References
https://cert-portal.siemens.com/productcert/html/ssa-032379.htmlhttps://git.kernel.org/stable/c/31a0ad2f60cb4816e06218b63e695eb72ce74974https://git.kernel.org/stable/c/33e974c2d5a82b2f9d9ba0ad9cbaabc1c8e3985fhttps://git.kernel.org/stable/c/67a05679621b7f721bdba37a5d18665d3aceb695https://git.kernel.org/stable/c/72777fc31aa7ab2ce00f44bfa3929c6eabbeaf48https://git.kernel.org/stable/c/c87bd4dd43a624109c3cc42d843138378a7f4548https://git.kernel.org/stable/c/d51e381beed5e2f50f85f49f6c90e023754efa12https://git.kernel.org/stable/c/f49161646e03d107ce81a99c6ca5da682fe5fb69https://git.kernel.org/stable/c/f57a4bd8d6cb5af05b8ac1be9098e249034639fbhttps://lists.debian.org/debian-lts-announce/2025/10/msg00007.htmlhttps://lists.debian.org/debian-lts-announce/2025/10/msg00008.html