Confluence Security Advisory 2007-11-27
In this advisory:
XSS Type 2 Vulnerabilities in Macros and Wiki Markup
Severity
Atlassian rates this vulnerability as high, according to the scale published in Confluence Security. The scale allows us to rank a vulnerability as critical, high, moderate or low.
Risk Assessment
We have identified and fixed some security flaws which may affect Confluence instances in a public environment. These flaws are XSS (cross-site scripting) vulnerabilities in some of Confluence's macros and Wiki Markup, which potentially allow a malicious user (hacker) to insert their own HTML tags or script into a Confluence page.
- The hacker might take advantage of this flaw to steal other users' session cookies or other credentials, by sending the credentials back to the hacker's own web server.
- The hacker's text and script might be displayed to other people viewing the Confluence page. This is potentially damaging to your company's reputation.
Atlassian recommends that you upgrade to Confluence 2.6.2 to fix the vulnerabilities described below.
You can read more about XSS attacks at cgisecurity, CERT and other places on the web.
Risk Mitigation
If you judge it necessary, you can disable public access (e.g. anonymous access and public signon) to your wiki until you have applied the necessary patch or upgrade. For even tighter control, you could restrict access to trusted groups only.
Vulnerability
The following macros are affected:
- {color}
- {panel}
- {section}
- {column}
- {code}
The Wiki Markup for inserting images (e.g. !myImage.png!) is also vulnerable to XSS exploitation.
Fix
The fix is to escape all user input, so that no user input is interpreted as HTML or CSS. In some cases we also perform stricter validation on the range of values a user can supply in an attribute.
These issues have been fixed in Confluence 2.6.2. For more information, please see CONF-9350.
Our thanks to Igor Minar, who reported this issue to Atlassian. We fully support the reporting of vulnerabilities and we appreciate his working with us towards identifying and solving the problem.
Please let us know what you think of the format of this security advisory and the information we have provided.