Medium severity · published Sep 15, 2026
CVE-2026-91956
FreeRDP before 3.31.0 Out-of-Bounds Read via URBDRC
6.5
CVSS
0.4%
EPSS
No
On KEV
Description
FreeRDP before 3.31.0 contains an out-of-bounds read vulnerability in the URBDRC channel's func_get_ep_desc function that indexes interface arrays by position instead of protocol field InterfaceNumber. A malicious RDP server can send a crafted SELECT_CONFIGURATION message with permuted InterfaceNumber values to read past allocated heap memory and crash the client.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 33% 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-2026-91956
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-91956
Exploit
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-hg4r-vv53-vwf8
Third Party Advisory
https://www.vulncheck.com/advisories/freerdp-before-3.31.0-out-of-bounds-read-via-urbdrc
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