CVE 2011-4924
Cross-site scripting (XSS) vulnerability in Zope 2.8.x before 2.8.12, 2.9.x before 2.9.12, 2.10.x before 2.10.11, 2.11.x before 2.11.6, and 2.12.x before 2.12.3, 3.1.1 through 3.4.1. allows remote attackers to inject arbitrary web script or HTML via vectors related to the way error messages perform sanitization. NOTE: this issue exists because of an incomplete fix for CVE-2010-1104
See the 
CVE page on Mitre.org
for more details.
