Out-of-bounds write in FreeRDP - #VU138640
Published: July 20, 2026
Vulnerability identifier: #VU138640
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: N/A
CWE-ID: CWE-787
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: FreeRDP
Affected software:
FreeRDP
FreeRDP
Detailed vulnerability description
The vulnerability allows a remote attacker to cause a heap-based buffer overflow in a paste consumer process.
The vulnerability exists due to an out-of-bounds write in CliprdrStream_Read when processing a server-supplied CB_FILECONTENTS_RESPONSE for an IStream::Read request. A remote attacker can send a crafted clipboard file contents response with an oversized length field to cause a heap-based buffer overflow in a paste consumer process.
This issue affects the Windows client path and user interaction is required to paste server-offered clipboard file contents.
Remediation
Install security update from vendor's website.