Launchpad.net

CVE 2011-1492

steps/utils/modcss.inc in Roundcube Webmail before 0.5.1 does not properly verify that a request is an expected request for an external Cascading Style Sheets (CSS) stylesheet, which allows remote authenticated users to trigger arbitrary outbound TCP connections from the server, and possibly obtain sensitive information, via a crafted request.

See the CVE page on Mitre.org for more details.