Vulnerability record · CVE-2026-91960 · published 15 September 2026
CVE-2026-91960: Freerdp integer overflow vulnerability
Freerdp · Freerdp
FreeRDP versions before 3.31.0 contain an integer overflow in WinPR's Stream_EnsureRemainingCapacity function that allows remote attackers to cause denial of service. A malicious RD Gateway peer can send a WebSocket Ping frame with a crafted 64-bit extended payload length to trigger integer wraparound, resulting in a double free that crashes the FreeRDP client during connection.
Description
FreeRDP versions before 3.31.0 contain an integer overflow in WinPR's Stream_EnsureRemainingCapacity function that allows remote attackers to cause denial of service. A malicious RD Gateway peer can send a WebSocket Ping frame with a crafted 64-bit extended payload length to trigger integer wraparound, resulting in a double free that crashes the FreeRDP client during connection.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:
Affected products
1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
| Link | Tags |
|---|---|
| https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-vccg-35r5-8jrf | ExploitMitigationVendor Advisory |
| https://www.vulncheck.com/advisories/freerdp-before-3.31.0-integer-overflow-double-free | Third Party Advisory |
| https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-vccg-35r5-8jrf | ExploitMitigationVendor Advisory |
Track CVE-2026-91960 inside VULONE
Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.
Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2026-91960), CISA KEV, FIRST EPSS (scores of 2026-09-28). This page is refreshed as NVD updates the record.