Local authentication bypass through undisclosed RDP flaw
Published Oct 14, 2025 · Updated Oct 14, 2025
Improper authentication in Microsoft Windows Remote Desktop Protocol allows local users to bypass RDP security controls. Microsoft has not published the specific RDP component or the incorrect authentication operation that accepts attacker input. Exploitation requires authorized local access and multiple unspecified conditions; the bypass can compromise confidentiality, integrity, and availability.
Summary
What happened
Improper authentication in Microsoft Windows Remote Desktop Protocol allows local users to bypass RDP security controls. Microsoft has not published the specific RDP component or the incorrect authentication operation that accepts attacker input. Exploitation requires authorized local access and multiple unspecified conditions; the bypass can compromise confidentiality, integrity, and availability.
The record
- CVE
- CVE-2025-55340
- Published
- Oct 14, 2025
- Updated
- Oct 14, 2025
- Vendor
- Microsoft
- Product
- Windows Server 2025 (Server Core installation)
- Classifications
- CWE-287
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Oct 14, 2025CVE publishedPublication date reported by the CVE source.
- Oct 14, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=10.0.26100.0 <10.0.26100.6899
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
No public exploit references are available in this record.
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo