Tried, Tested and Proven

Security Advisory 06 – 036 – A potential phishing attack via the comments mechanism

Vulnerable System:

Movable Type

Vulnerability discovery and development:

Portcullis Security Testing Services.

Credit for Discovery:

Tim Brown – Portcullis Computer Security Ltd.

Affected Systems:

All known versions of Movable Type, the vulnerability was discovered for version 3.16.


By posting a comment to an entry on a blog, it is possible to create URLs within the web server domain which actually forward anyone who requests them to a URL on another web server by entering a URL with the comment. Comments that include a URL will be added to the blog entry with the URL encoded as http://webserver/path/to/mt-comments.cgi?__mode=red;id=[id] which forwards any user who requests the URL using JavaScript to the URL referenced by the id.


By forwarding this URL, which may be seen as trusted an attacker may be able to lure its recipients to a malicous site of their creation.


Exploit code is not required.


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