What’s Vulnerable › Vulnerabilities

CVE-2026-109952: FreeRDP 3.0.0 before 3.32.0 Security Protocol Downgrade via Negotiation Response

• Severity: medium (CVSS 5.3 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2026-10-13 · updated 2026-10-21
• Weakness: CWE-757

Description

The FreeRDP client 3.0.0 before 3.32.0 does not check a server-selected PROTOCOL_RDSTLS or PROTOCOL_HYBRID_EX against its enabled protocol set in nego_process_negotiation_response(), allowing a security protocol downgrade. A malicious server or man-in-the-middle can select RDSTLS to override /sec:nla pinning, complete authentication with an all-zero cookie, and receive the user's cleartext password in the Client Info PDU.

Affected products

• FreeRDP: from 3.0.0 before 3.32.0 — fixed in 3.32.0

How to fix

Upgrade to a fixed version: FreeRDP 3.32.0. Check the vendor advisory for mitigations.

References

• https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qq23-mqmv-pc65
• https://www.vulncheck.com/advisories/freerdp-3.0.0-before-3.32.0-security-protocol-downgrade-via-negotiation-response
• https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qq23-mqmv-pc65

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