CVE-2026-91955
HIGHDescription
FreeRDP before 3.31.0 fails to validate client-supplied DesktopWidth and DesktopHeight values during GCC negotiation, allowing remote attackers to crash the server. Attackers can send crafted RDP packets with zero or oversized dimensions to trigger division-by-zero or assertion failures in multifragment update capability calculations, terminating the server process.
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:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Exploit Intelligence
Moderate risk: more likely to be exploited than 47% of all known CVEs.
References
Related Vulnerabilities
Other CWE-369 vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2012-0207 | High | 7.5 | 20% | - | Fix |
| CVE-2017-8537 | Medium | 5.5 | 17% | - | - |
| CVE-2017-8536 | Medium | 5.5 | 17% | - | - |
| CVE-2017-8535 | Medium | 5.5 | 17% | - | - |
| CVE-2007-2237 | Medium | 5.5 | 15% | - | - |
| CVE-2025-0317 | High | 7.5 | 14% | - | - |
Common questions
How do I fix CVE-2026-91955?
Upgrade freerdp3 on debian unstable to 3.31.0+dfsg-1 or later.
Is CVE-2026-91955 being actively exploited?
Not that we know of. CVE-2026-91955 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 0.57% is the estimated probability that it will be exploited in the next 30 days. That is higher than 47% of all scored CVEs.
How severe is CVE-2026-91955?
CVE-2026-91955 has a CVSS v3 base score of 7.5, rated high. 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-2026-91955 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-2026-91955
Markdown
[](https://tridentstack.com/cve/CVE-2026-91955)HTML
<a href="https://tridentstack.com/cve/CVE-2026-91955"><img src="https://tridentstack.com/cve/badge/CVE-2026-91955.svg" alt="CVE-2026-91955"></a>Check your Linux endpoints for this class of vulnerability
TridentStack Control continuously scans Linux endpoints for known vulnerabilities and deploys the fixes from the same console. 200 endpoints free forever, no credit card.
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 2026-09-24.