AntiSamy is a library for performing fast, configurable cleansing of HTML coming from untrusted sources. Prior to version 1.7.4, there is a potential for a mutation XSS (mXSS) vulnerability in AntiSamy caused by flawed parsing of the HTML being sanitized. To be subject to this vulnerability the preserveComments
directive must be enabled in your policy file and also allow for certain tags at the same time. As a result, certain crafty inputs can result in elements in comment tags being interpreted as executable when using AntiSamy's sanitized output. This issue has been patched in AntiSamy 1.7.4 and later.