SB2025011458 - Multiple vulnerabilities in Microsoft Windows Remote Desktop Gateway (RD Gateway)

Description

This security bulletin contains information about 2 vulnerabilities.

1) Race condition (CVE-ID: CVE-2025-21278)

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear

The vulnerability allows a local attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a race condition in Windows Remote Desktop Gateway (RD Gateway). A local attacker can exploit the race and cause a denial of service condition on the target system.

2) Type Confusion (CVE-ID: CVE-2025-21225)

CWE-ID: CWE-843 - Type confusion

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a type confusion error in Windows Remote Desktop Gateway (RD Gateway). A remote attacker can pass specially crafted data to the application, trigger a type confusion error and cause a denial of service on the target system.

Remediation

Install update from vendor's website.

References

• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2025-21278
• https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2025-21225