oCERT-2011-001 Chyrp input sanitization errors

Description:

The Chyrp framework, an open source blogging engine, suffers from cross-site scripting (XSS) and local file inclusion (LFI) vulnerabilities.

Insufficient input sanitization on the parameters passed to pages related to administration settings, the javascript handler and the index handler leads to arbitrary javascript injection in the context of the user session. This could be potentially exploited to hijack the session of the administrator.

Insufficient path sanitization on the root 'action' query string parameter leads to inclusion of arbitrary files from local sources, this could be exploited to read arbitrary accessible files on the hosting server filesystem and potentially execute arbitrary commands or code.

Affected version:

Chyrp <= 2.1

Fixed version:

Chyrp, N/A

Credit: vulnerability report and PoC code received from Eldar Marcussen <wireghoul [at] justanotherhacker [dot] com>.

CVE: CVE-2011-2743 (XSS), CVE-2011-2744 (LFI)

Timeline:

2011-05-17: vulnerability report received
2010-05-17: contacted chyrp maintainers
2010-07-13: oCERT advisory published jointly with reporter advisory
2010-07-14: assigned CVE

References:
http://www.justanotherhacker.com/advisories/JAHx113.txt