T1151: Space after Filename
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 [1].
Adversaries can use this feature to trick users into double clicking benign-looking files of any format and ultimately executing something malicious.
This ATT&CK object is revoked or deprecated in the current MITRE ATT&CK release.
It remains available for historical context and inbound links. Use current ATT&CK relationships and replacement guidance before basing detection or reporting work on this page.
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Space after Filename
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 [1].
Adversaries can use this feature to trick users into double clicking benign-looking files of any format and ultimately executing something malicious.
How security teams should use this page
Treat this object as behavior context, not an attribution claim. Validate the related groups, software, data sources, and mitigations against official ATT&CK relationships and your own telemetry before making control-coverage decisions.
Related techniques
This mirrors the MITRE pattern of making group, software, campaign, and technique relationships scannable. Relationship notes come from mirrored ATT&CK relationship text when available.
| Domain | ID | Name | Relationship / procedure |
|---|---|---|---|
| Enterprise | T1036.006 | Space after FilenameSub-technique | This object revoked by Space after Filename. |
All related ATT&CK context
Object version and sync metadata
The fields below describe the current mirrored snapshot. When Glexia retains multiple ATT&CK source imports, you can open the table to compare the same object across releases (hashes and MITRE timestamps). For MITRE’s own release notes and roadmap, see ATT&CK resources — Updates.
Imported snapshots across ATT&CK releases(1)
| Release | Bundle imported | Object version | Modified | Status | Raw hash |
|---|---|---|---|---|---|
| 19.1 | 1.1 | Current bundleRevoked | fef1d4065026… |
Mirrored ATT&CK source object
The raw object is retained through the mirrored ATT&CK source bundle and object hash. The raw endpoint returns the exact object from the mirrored bundle when available.
External references and citations
MITRE external references are preserved separately from Glexia analysis so citations remain traceable to their original source records.
- [1]Mac Backdoors are back
Dan Goodin. (2016, July 6). After hiatus, in-the-wild Mac backdoors are suddenly back. Retrieved July 8, 2017.
Open source URL - [2]Mac Backdoors are back
Dan Goodin. (2016, July 6). After hiatus, in-the-wild Mac backdoors are suddenly back. Retrieved July 8, 2017.
Open source URL - [3]Mac Backdoors are back
Dan Goodin. (2016, July 6). After hiatus, in-the-wild Mac backdoors are suddenly back. Retrieved July 8, 2017.
Open source URL - [4]capecCAPEC-649Open source URL
- [5]capecCAPEC-649Open source URL
- [6]capecCAPEC-649Open source URL
- [7]mitre-attackT1151Open source URL
- [8]mitre-attackT1151Open source URL
- [9]mitre-attackT1151Open source URL
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