Daniel Fabian has reported a vulnerability in Motorola Wireless Router WR850G, which can be exploited by malicious people to bypass user authentication and hijack an administrators session.

The vulnerability is caused due to an error in the session handling. This can be exploited to hijack an administrator's session by accessing e.g. the "/ver.asp" page directly when an administrator logs in.

Successful exploitation discloses sensitive information and allows execution of arbitrary commands with administrative privileges.

NOTE: On exploitation, the administrator will receive the message "403 Only one login allowed The existing client:[ip]".

The vulnerability has been reported in firmware version 4.03. Other versions may also be affected.

Solution
Update to firmware version 5.13:
Further details available in Customer Area

Provided and/or discovered by
Daniel Fabian

Changelog
Further details available in Customer Area

Deep Links
Links available in Customer Area