SB2026051303 - Privilege escalation in Microsoft Windows Remote Desktop Services
Published: May 13, 2026
Security Bulletin ID
SB2026051303
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local 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-2026-40398)
CWE-ID: CWE-122 - Heap-based Buffer Overflow
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to escalate privileges on the target system.
The vulnerability exists due to a boundary error in Windows Remote Desktop Services. A local user can pass specially crafted data to the application, trigger a heap-based buffer overflow and gain elevated privileges on the system.
Remediation
Install update from vendor's website.