SB20261111129 - Heap-based buffer overflow in Microsoft GDK
Published: November 11, 2026
Security Bulletin ID
SB20261111129
CSH Severity
High
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Remote access
Highest impact
Code execution
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Heap-based buffer overflow (CVE-ID: CVE-2026-66801)
CWE-ID: CWE-122 - Heap-based Buffer Overflow
CVSSv4: 9.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to a heap-based buffer overflow in an Xbox network service when processing network packets. A remote attacker can send a specially crafted packet to the affected service to execute arbitrary code on the target system.
Remediation
Install update from vendor's website.