Medium severity · published Sep 15, 2026
CVE-2026-91958
FreeRDP 3.11.0 through 3.30.0 Heap Buffer Overflow via Monitor Index
6.6
CVSS
0.2%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
Low
Integrity
Low
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 9% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
FreeRDP · FreeRDP
3.11.0 before 3.31.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-91958
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-91958
Exploit
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-23pf-q83q-x45r
Third Party Advisory
https://www.vulncheck.com/advisories/freerdp-3.11.0-through-3.30.0-heap-buffer-overflow-via-monitor-index
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