Out-of-bounds Read in Linux

CVE-2026-31558

In the Linux kernel, the following vulnerability has been resolved: LoongArch: KVM: Make kvm_get_vcpu_by_cpuid() more robust kvm_get_vcpu_by_cpuid() takes a cpuid parameter whose type is int, so cpuid can be negative. Let kvm_get_vcpu_by_cpuid() return NULL for this case so as to make it more robust. This fix an out-of-bounds access to kvm_arch::phyid_map::phys_map[].

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.002 (6.3th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 6th percentile — 6.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-31558: held from 0.001 to 0.002.

EPSS over last 30 days · oldest: 0.001 · newest: 0.002 · change: +0.000

Affected products

  • Linux — versions 73516e9da512adc63ba3859fbd82a21f6257348f, 6.10, 0
  • Linux Kernel — versions 6.10, 7.0

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-31558?
CVE-2026-31558 is a high-severity vulnerability in Linux, classified under Out-of-bounds Read. CVSS score: 8.8/10. Published 2026-04-24.
How severe is CVE-2026-31558?
High severity. CVSS v3 base score is 8.8 out of 10.