T1151
About this technique
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.
Read the full ATT&CK description
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 (Citation: Mac Backdoors are back).
Adversaries can use this feature to trick users into double clicking benign-looking files of any format and ultimately executing something malicious.
Curated incident relationships
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Daily items linked through predicted CVEs
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Predicted CVE associations
These backfilled or model-produced candidates come from the current triage artifact. They are informational, not official MITRE mappings.