CVE 2015-5345
The Mapper component in Apache Tomcat 6.x before 6.0.45, 7.x before 7.0.68, 8.x before 8.0.30, and 9.x before 9.0.0.M2 processes redirects before considering security constraints and Filters, which allows remote attackers to determine the existence of a directory via a URL that lacks a trailing / (slash) character.
See the 
CVE page on Mitre.org
for more details.
