Vulnerabilities

Vulnerability · CVE-2026-35420

Heap-based buffer overflow in Windows Kernel allows an authorized attacker to elevate privileges locally.

Published May 12, 2026 · catalog updated Jun 17, 2026 · windows server 2012

Check if you run it

No confirmed exploitation is on record for CVE-2026-35420. EPSS is 0.33%. Act only if a listed version of windows server 2012 is installed.

Gaps on this record

  • No version range is stored. A customer cannot check an installed version against this record.
  • No vendor fix or required action is stored. Compare the linked advisory before you change production.
Severity
High7.8
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.33%
Remediation
Advisory link
Affected products
cpe microsoft/windows server 2012 · cpe microsoft/windows server 2016 · cpe microsoft/windows server 2019 · cpe microsoft/windows server 2022 · cpe microsoft/windows server 2022 23h2 · cpe microsoft/windows server 2025

Heap-based buffer overflow in Windows Kernel allows an authorized attacker to elevate privileges locally.

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • cpe microsoft/windows server 2012r2
  • cpe microsoft/windows server 2016version unspecified
  • cpe microsoft/windows server 2019version unspecified
  • cpe microsoft/windows server 2022version unspecified
  • cpe microsoft/windows server 2022 23h2version unspecified
  • cpe microsoft/windows server 2025version unspecified

How to fix CVE-2026-35420

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2026-35420. EPSS is 0.33%. Act only if a listed version of windows server 2012 is installed.

Which versions are affected?

Compare what you have installed with microsoft/windows server 2012 r2. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

CWE-122: Heap-based Buffer Overflow. EPSS 0.33%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Technology hubs

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. May 12, 2026 · NIST NVD

    Detected

    Heap-based buffer overflow in Windows Kernel allows an authorized attacker to elevate privileges locally.

  2. Jun 17, 2026 · NIST NVD

    Updated

    Heap-based buffer overflow in Windows Kernel allows an authorized attacker to elevate privileges locally.

Sources

  • CVE.orgVulnerability recordCVE-2026-35420

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2026-35420

    30-day exploitation probability 0.3%

    first.org
  • NIST NVDVulnerability recordCVE-2026-35420

    Heap-based buffer overflow in Windows Kernel allows an authorized attacker to elevate privileges locally.

    nvd.nist.gov

References

Freshness

Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.