Executive brief
RustDesk, a popular open-source remote desktop software, contains a security flaw that allows users with limited 'File Transfer' permissions to bypass their restrictions. An attacker who has been granted access only to move files can take full control of the remote computer, including moving the mouse, typing on the keyboard, and capturing screenshots. This effectively upgrades a limited file-sharing session into a full unauthorized remote control session, potentially leading to data theft or full system compromise.
Technical details
RustDesk suffers from an incorrect authorization vulnerability (CWE-863) where incoming control messages are gated based on per-capability flags rather than the specific authorized connection type of the active session. Specifically, file-transfer sessions fail to clear or properly isolate these capability flags. A remote attacker with valid FileTransfer credentials can exploit this logic flaw to inject HID events (keyboard and mouse input) and access unguarded screenshot and display-capture handlers. This allows for a complete privilege escalation from a restricted file-transfer role to full remote desktop control. The vulnerability is present in versions up to git commit ff226f6d8013dee2de5a6553abaf67bf32b3e875.
Affected products
- RustDesk RustDesk <= ff226f6d8013dee2de5a6553abaf67bf32b3e875 (git)
Timeline
- 2026-06-28: advisory
- 2026-06-28: disclosed