CVE-2026-109952
MEDIUMDescription
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.
How to fix
TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N
Exploit Intelligence
Low risk: more likely to be exploited than 25% of all known CVEs.
References
Related Vulnerabilities
Other CWE-757 vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2020-10135 | Medium | 5.4 | 2.4% | - | Fix |
| CVE-2017-9269 | High | 7.7 | 2.2% | - | Fix |
| CVE-2021-36326 | Medium | 6.5 | 1.2% | - | Fix |
| CVE-2025-24154 | Critical | 9.1 | 1.2% | - | Fix |
| CVE-2019-14887 | Critical | 9.1 | 1.1% | - | - |
| CVE-2017-9267 | Medium | 6.5 | 1.0% | - | Fix |
Common questions
How do I fix CVE-2026-109952?
Upgrade freerdp3 on debian unstable to 3.32.0+dfsg-1 or later.
Is CVE-2026-109952 being actively exploited?
Not that we know of. CVE-2026-109952 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 0.32% is the estimated probability that it will be exploited in the next 30 days. That is higher than 25% of all scored CVEs.
How severe is CVE-2026-109952?
CVE-2026-109952 has a CVSS v3 base score of 5.3, rated medium. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.
What does CVE-2026-109952 affect?
Published advisories record a fix for freerdp3 (Debian). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.
Embed a live status badge for CVE-2026-109952
Markdown
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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-10-21.