CVE-2026-40254
Medium
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.
SeverityMedium
CVSS4.2
Exploit probability—
ProductFreerdp
PublishedApr 24, 2026
First seenApr 24, 2026
Weakness typeCWE-193CWE-193
How to fix
Update
- freerdp freerdp3.25.0 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| freerdp freerdp | v < 3.25.0 | 3.25.0 |
Check your version
Choose the product and enter the version you run to see whether it falls in the affected range.
In the Intelligence 360 plan
Attack Surface Management
See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.