SS-2015-009: XSS In rewritten hash links
- Important (?)
- Versions Affected:
- 3.0.12 and below, 3.1.0 - 3.1.11
- Versions Fixed:
- 3.0.13, 3.1.12
- Release Date:
A high level XSS vulnerability has been discovered in the SilverStripe framework which causes links containing hash anchors (E.g. href="#anchor") to be rewritten in an unsafe way.
The rewriteHashlinks option on SSViewer will rewrite these to contain the current url, although without adequate escaping, meaning that HTML could be injected via injecting unsafe values to any page via the querystring.
Due to the nature of this issue it is likely that a large number of SilverStripe sites are affected.
Special credit to Dariusz Półtorak for reporting the issue and providing us with lots of helpful information, as well as the "Happy Endians" team, part of CP DDB.