Insert Dylib Fixed
For custom apps:
DYLD_INSERT_LIBRARIES=/path/to/inject.dylib /Applications/TargetApp.app/Contents/MacOS/TargetApp
In the Apple ecosystem, the dynamic linker (known as dyld ) is responsible for loading shared libraries into a process's address space. There are two primary methods for "inserting" a dylib:
# Syntax: insert_dylib --all-yes --weak /path/to/inject.dylib /path/to/TargetApp insert_dylib --weak /path/to/inject.dylib /Applications/TargetApp.app/Contents/MacOS/TargetApp
for (uint32_t i = 0; i < _dyld_image_count(); i++) const char *name = _dyld_get_image_name(i); if (is_dylib_blacklisted(name)) fprintf(stderr, "Suspicious dylib loaded: %s\n", name); exit(1);
:
Replace legit dylibs by altering search path:
codesign --remove-signature /Applications/TargetApp.app/Contents/MacOS/TargetApp codesign -s - /Applications/TargetApp.app/Contents/MacOS/TargetApp
Monitor task_for_pid() calls using EndpointSecurity framework.
Every macOS executable (Mach-O file) contains a series of "Load Commands" in its header. These commands instruct dyld on what libraries are required to run the app (e.g., LC_LOAD_DYLIB for system frameworks). By adding a new load command pointing to a custom dylib, we can force the app to load our code every time it launches.
