T1099

Adversaries may modify file time attributes to hide new or changes to existing files. Timestomping is a technique that modifies the timestamps of a file (the modify, access, create, and change times), often to mimic files that are in the same folder. This is done, for example, on files that have been modified or created by the adversary so that they do not appear conspicuous to forensic investigators or file analysis tools.

Adding it as PBA:
- LINUX: create a temp file, change its last-modified timestamp (see this); remove temp file

- WINDOWS: create a temp file, change its last-modified timestamp (see this); remove temp file

Mapping the technique to the ATT&CK matrix