Medium severity · published Sep 15, 2026
CVE-2026-91951
FreeRDP 3.14.0 through 3.30.0 Out-of-bounds Write via urbdrc
6.5
CVSS
0.4%
EPSS
No
On KEV
Description
FreeRDP versions before 3.31.0 contain an out-of-bounds write vulnerability in the urbdrc client channel's urb_send_current_frame_number_result() function. A malicious RDP server can send a crafted 28-byte USB redirection message to trigger a 4-byte write past the allocated 16-byte buffer, causing denial of service when verbose asserts are enabled.
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 32% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FR
FreeRDP · FreeRDP
3.14.0 before 3.31.0 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-91951
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-91951
Exploit
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-h5w2-q35j-443h
Third Party Advisory
https://www.vulncheck.com/advisories/freerdp-3.14.0-through-3.30.0-out-of-bounds-write-via-urbdrc
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