CVE-2026-40254

FreeRDP: contains_dotdot() off-by-one allows drive channel path traversal via terminal ..

State: Published
Severity: 4.2 Medium
Published: Apr 24, 2026
Updated: Apr 24, 2026
Reserved: Apr 10, 2026

Description

FreeRDP is a free implementation of the Remote Desktop Protocol. Versions prior to 3.25.0 have an off-by-one in the path traversal filter in `channels/drive/client/drive_file.c`. The `contains_dotdot()` function catches `../` and `..\` mid-path but misses `..` when it's the last component with no trailing separator. A rogue RDP server can read, list, or write files one directory above the client's shared folder through RDPDR requests. This requires the victim to connect with drive redirection enabled. Version 3.25.0 patches the issue.

Scores

CVSS	Score	Vector	Source
3.1	4.2 Medium	CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:L/A:N	GitHub_M

Weaknesses

CWE-193 Off-by-one Error

Affected Products

Product	Versions
FreeRDPFreeRDP	< 3.25.0Affected

References

https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-3xpj-m4hx-8vmx

Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.