Vulnerable Systems:
* TCPDF versions from 4.5.036 (2009-04-03) to 4.9.005 (2010-04-01)
Immune Systems:
* TCPDF version 4.9.006 (2010-04-02)
To exploit this issue the application that is using TCPDF must be vulnerable to cross-site scripting inside their pdf generating code.
The problem is caused by the TCPDF callback element that could be injected into HTML code. The parsing of the callback element is using the 'params' attribute inside an eval() statement without any sanitation.
The injection of the following TCPDF callback element into HTML code (that is processed by TCPDF) will exploit the issue:
Disclosure Timeline:
2010-04-02 - Vendor notified
2010-04-02 - Vendor reaction and security fix
2010-04-08 - Public disclosure (with vendor permissions)