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TI-2026-73207 Aliases CVE-2026-97803GHSA-r87q-3xpf-cqh6

Heap-based buffer overflow in Windows Kernel allows privilege escalation

Priority LOW 36CWE-122Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-122 and the CVSS impact.

Summary

Microsoft Windows 11 version 26H1 from 10.0.28000.0 before 10.0.28000.3231 is affected. A heap-based buffer overflow in the Windows Kernel lets an authorized attacker escalate privileges locally (CWE-122). A local attacker with low privileges can gain higher privileges, with no user interaction needed.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

Description from the CNA

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

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00353 29th percentileScored 2026-11-07
Fix Fixed Windows 11 version 26H1 (Microsoft): 10.0.28000.3231

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
MicrosoftWindows 11 version 26H110.0.28000.0 to before 10.0.28000.323110.0.28000.3231Patch availableCNA
  • Windows 11 version 26H1 VendorMicrosoft Affected 10.0.28000.0 to before 10.0.28000.3231 Fixed in 10.0.28000.3231 Patch available CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:arm64:*before 10.0.28000.3231VulnerableMicrosoft
cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:x64:*before 10.0.28000.3231VulnerableMicrosoft
  • cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:arm64:* Versions before 10.0.28000.3231 Vulnerable ·Microsoft
  • cpe:2.3:o:microsoft:windows_11_26h1:*:*:*:*:*:*:x64:* Versions before 10.0.28000.3231 Vulnerable ·Microsoft

Remediation

Microsoft Windows 11 version 26H1 is fixed in 10.0.28000.3231.

Written with Claude Haiku 5.5 from the sources below · 2026-10-28

  • Fix · CNA Windows 11 version 26H1 (Microsoft) Fixed in 10.0.28000.3231

Timeline

  1. 2026-10-13 Threatist record created from CVE-2026-97803
  2. 2026-10-13 Alias added: GHSA-r87q-3xpf-cqh6
  3. 2026-10-14 CISA SSVC decision points changed
  4. 2026-10-14 Priority changed: MEDIUM → LOW

References

Patch 1

  • TI-2026-26194 Windows Internet Key Exchange (IKE) Service Extensions Remote Code Execution Vulnerability KEVCVSS 3.1CRITICAL 9.8
  • TI-2026-73128 Windows Shell Security Feature Bypass Vulnerability KEVCVSS 3.1HIGH 8.8
  • TI-2026-56567 Windows Update Stack Elevation of Privilege Vulnerability KEVCVSS 3.1HIGH 7.8
  • TI-2026-48395 Windows Ancillary Function Driver for WinSock Elevation of Privilege Vulnerability KEVCVSS 3.1HIGH 7.0
  • TI-2026-24734 Windows Shell Spoofing Vulnerability KEVCVSS 3.1MEDIUM 4.3
  • TI-2026-36364 HTTP.sys Denial of Service Vulnerability CVSS 3.1HIGH 7.5
See all 2533 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences