Medium severity · published Oct 13, 2026
CVE-2026-109952
FreeRDP 3.0.0 before 3.32.0 Security Protocol Downgrade via Negotiation Response
5.3
CVSS
0.3%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.3% · higher than 25% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
FreeRDP · FreeRDP
3.0.0 before 3.32.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-109952
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-109952
vendor-advisory
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-qq23-mqmv-pc65
third-party-advisory
https://www.vulncheck.com/advisories/freerdp-3.0.0-before-3.32.0-security-protocol-downgrade-via-negotiation-response
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