Improper Access Control
Citrix NetScaler AppFirewall, as used in NetScaler 10.5, allows remote attackers to bypass intended firewall restrictions via a crafted Content-Type header, as demonstrated by the application/octet-stream and text/xml Content-Types.
CWE-284 - Improper Access Control
Listed 5th in the 'OWASP Top Ten', improper (or broken) access control attacks are a fundamental type of vulnerability. This includes a broad range of design flaws that enable users to act outside of their intended permissions. They can use these privileges to gain access to restricted files and functionality such as accessing restricted information, falsifying records, destroying data, or executing commands.