Sub-technique of T1036 Masquerading.View on attack.mitre.org
Adversaries can hide a program's true filetype by changing the extension of a file. With certain file types (specifically this does not work with .app extensions), appending a space to the end of a filename will change how the file is processed by the operating system.
For example, if there is a Mach-O executable file called evil.bin, when it is double clicked by a user, it will launch Terminal.app and execute. If this file is renamed to evil.txt, then when double clicked by a user, it will launch with the default text editing application (not executing the binary). However, if the file is renamed to evil.txt (note the space at the end), then when double clicked by a user, the true file type is determined by the OS and handled appropriately and the binary will be executed .
Adversaries can use this feature to trick users into double clicking benign-looking files of any format and ultimately executing something malicious.
Rules on DetectionCode tagged with T1036.006.
| Rule | Level | Log source |
|---|---|---|
| Space After Filename - macOS | low | macos / process_creation |
None recorded.
| Used by | Procedure example |
|---|---|
| GroupAPT38 | APT38 has put several spaces before a file extension to avoid detection and suspicion. |
Data from MITRE ATT&CK® (Enterprise). ATT&CK® is a registered trademark of The MITRE Corporation.
