High severity · published Sep 15, 2026
CVE-2026-91955
FreeRDP before 3.31.0 Denial of Service via Desktop Dimensions
7.5
CVSS
0.6%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.6% · higher than 47% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
FreeRDP · FreeRDP
before 3.31.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-91955
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-91955
Exploit
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-4464-r7qj-pgrx
Exploit
https://www.vulncheck.com/advisories/freerdp-before-3.31.0-denial-of-service-via-desktop-dimensions
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