CVE-2026-91958

FreeRDP versions before 3.31.0 fail to validate MonitorIds array values when parsing RDP connection files, allowing unbounded array indexing in xf_detect_monitors. Attackers can craft a malicious RDP file with an out-of-range selectedmonitors value to trigger out-of-bounds heap read and write operations when opened in xfreerdp.

CVSS v3 6.6 MEDIUM

6.6^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 4.7

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-23pf-q83q-x45r	Exploit Mitigation Vendor Advisory
https://www.vulncheck.com/advisories/freerdp-3.11.0-through-3.30.0-heap-buffer-overflow-via-monitor-index	Third Party Advisory
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-23pf-q83q-x45r	Exploit Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:freerdp:freerdp:*:*:*:*:*:*:*:*

History

24 Sep 2026, 12:17

Type	Values Removed	Values Added
References	~~() https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-23pf-q83q-x45r -~~	() https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-23pf-q83q-x45r - Exploit, Mitigation, Vendor Advisory
References	~~() https://www.vulncheck.com/advisories/freerdp-3.11.0-through-3.30.0-heap-buffer-overflow-via-monitor-index -~~	() https://www.vulncheck.com/advisories/freerdp-3.11.0-through-3.30.0-heap-buffer-overflow-via-monitor-index - Third Party Advisory
CPE		cpe:2.3:a:freerdp:freerdp::::::::
First Time		Freerdp freerdp Freerdp

Information

Published : 2026-09-15 16:17

Updated : 2026-09-24 12:17

NVD link : CVE-2026-91958

Mitre link : CVE-2026-91958

CVE.ORG link : CVE-2026-91958

JSON object : View

Products Affected

freerdp

freerdp

CWE

CWE-125

Out-of-bounds Read

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