{"id":"CVE-2026-91955","title":"FreeRDP before 3.31.0 fails to validate client-supplied DesktopWidth and DesktopHeight values during GCC negotiation, allowing remote attackers to crash the server","summary":"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…","severity":"high","cvss":7.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","cwe":["CWE-369"],"vendor":"FreeRDP","product":"FreeRDP","affected":["FreeRDP < 3.31.0"],"published":"2026-09-15","updated":"2026-09-16","sourceUpdated":"2026-09-16T20:15:36.037","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-91955","references":[{"url":"https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-4464-r7qj-pgrx","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/freerdp-before-3.31.0-denial-of-service-via-desktop-dimensions","label":"disclosure@vulncheck.com"},{"url":"https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-4464-r7qj-pgrx","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-91955.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-91955"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2533907"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-91955"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-91955"}],"tags":["nvd","cve.org","exploit-available","csaf","vex","red-hat"],"exploitAvailable":true,"ssvc":{"exploitation":"poc","automatable":"yes","technicalImpact":"partial","timestamp":"2026-09-15T15:54:25.986513Z"},"ingestedAt":"2026-09-15T15:39:12.919Z","epss":0.00452,"epssPercentile":0.38509,"slug":"CVE-2026-91955","body":"## Overview\n\nFreeRDP 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Important · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, … · updated 2026-09-15 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-91955.json)","depth":"midnight","depthScore":53,"depthScoreParts":{"impact":41.3,"likelihood":0.1,"exploitation":12,"ransomware":0},"changes":[{"seq":204279,"id":"CVE-2026-91955","ts":1789490444071,"field":"exploit_available","old":"false","new":"true"}]}