Typo3 Vulnerable to Cache Poisoning

Problem Description: A request URL with arbitrary arguments, but still pointing to the home page of a TYPO3 installation can be cached if the configuration option config.prefixLocalAnchors is used with the values “all” or “cached”. The impact of this vulnerability is that unfamiliar looking links to the home page can end up in the cache, which leads to a reload of the page in the browser when section links are followed by web page visitors, instead of just directly jumping to the requested section of the page. TYPO3 versions 4.6.x and higher are only affected if the homepage is not a shortcut to a different page.

Solution: Removing the configuration options config.prefixLocalAnchors (and optionally also config.baseUrl) in favor of config.absRefPrefix

Credits: Thanks to Gernot Leitgab who discovered and reported the vulnerability.