CVE-2026-68579

FreeRDP before 3.30.0 (<= 3.29.0) contains a heap-based buffer overflow in the Windows clipboard client's CliprdrStream_Read function (client/Windows/wf_cliprdr.c). When an OLE paste consumer (e.g. explorer.exe) calls IStream::Read with a fixed-size buffer of cb bytes, CliprdrStream_Read requests file contents from the RDP server and then copies the response into the caller's buffer using the server-supplied length (req_fsize) instead of cb. A malicious or compromised RDP server can return an oversized CB_FILECONTENTS_RESPONSE, causing an out-of-bounds write of attacker-controlled data into the paste consumer's heap buffer when a user pastes server-offered clipboard file contents.

CVSS v3 9.6 CRITICAL

9.6^/10

CVSS v3 : CRITICAL

Vector :

Exploitability : 2.8 / Impact : 6.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact HIGH

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://github.com/FreeRDP/FreeRDP/commit/5e8e987b469b60a3bafadf8f5afc40f91c09f458
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-m37j-jcr2-8gcc
https://www.vulncheck.com/advisories/freerdp-before-heap-overflow-via-cliprdrstream-read

Configurations

No configuration.

History

02 Aug 2026, 13:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-08-02 13:16

Updated : 2026-08-03 17:16

NVD link : CVE-2026-68579

Mitre link : CVE-2026-68579

CVE.ORG link : CVE-2026-68579

JSON object : View

Products Affected

No product.

CWE

CWE-787

Out-of-bounds Write

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