CVE-2026-31558

High

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[].

Package Linux Kernel
Published 2026-04-24
Last modified 2026-04-27
CVSS version 3.1
Patch available
Yes

CVSS 3.1 score

8.8

out of 10
High
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Changed
Confidentiality
High
Integrity
High
Availability
High
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Weakness type

CWE-125

CVE-2026-31558 is a Out-of-bounds Read vulnerability

What is Out-of-bounds Read?

The product reads data past the end or before the beginning of the intended buffer. Learn more on MITRE CWE

Affected versions

Linux kernel versions 6.10 and later are affected. Fixed in 6.12.80, 6.18.21, 6.19.11, 7.0 and their respective stable series.

Affected from
≥ 6.10
Fixed in
✓ 6.12.80 6.12.x ✓ 6.18.21 6.18.x ✓ 6.19.11 6.19.x ✓ 7.0

References

The following references provide additional information about CVE-2026-31558 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Frequently asked questions

  • What is CVE-2026-31558?

    CVE-2026-31558 is a High severity Linux kernel vulnerability with a CVSS score of 8.8 out of 10 , classified as an Out-of-bounds Read flaw (CWE-125) . It affects Linux kernel versions from 6.10 onward and has been patched in 6.12.80, 6.18.21, 6.19.11 and others. CVE-2026-31558 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • What is the CVSS score for CVE-2026-31558?

    CVE-2026-31558 has a CVSS score of 8.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H .

  • Is there a patch available for CVE-2026-31558?

    Yes — CVE-2026-31558 has been patched. Fixed versions include 6.12.80, 6.18.21, 6.19.11 and others. If you are running Linux kernel 6.10 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2026-31558 actively exploited?

    No — CVE-2026-31558 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

  • What is Out-of-bounds Read (CWE-125)?

    The product reads data past the end or before the beginning of the intended buffer. View CWE-125 on MITRE CWE →