An issue was discovered in Znuny and Znuny LTS 6.0.31 through 6.5.7 and Znuny 7.0.1 through 7.0.16 where a logged-in user can upload a file (via a manipulated AJAX Request) to an arbitrary writable location by traversing paths. Arbitrary code can be executed if this location is publicly available through the web server.
The product constructs all or part of a code segment using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the syntax or behavior of the intended code segment.