Identifier / Programs / Linux and Unix
strace
Troubleshooting tool for tracing system calls. tldr-pages
GTFOBins file-write, shell 1 ATT&CK technique 2 documented commands
How strace is abused
file-write
-s-oshell T1059.004 Command and Scripting Interpreter: Unix Shell
-oEach abuse is GTFOBins's category and the options and words it uses; the full write-up is on GTFOBins's page for strace.
2 documented commands
file-write unprivileged, with sudo
The data to be written appears amid the syscall log, quoted and with special characters escaped in octal notation. The string representation will be truncated, pick a value big enough instead of 999. More generally, any binary that executes whatever syscall passing arbitrary data can be used in place of strace - DATA.
strace -s 999 -o /path/to/output-file strace - DATAshell unprivileged, with sudo, as SUID
strace -o /dev/null /bin/shAs SUID:
strace -o /dev/null /bin/sh -pNone of the 2 commands the identifier reads trips a Sigma process-creation rule. These commands are, with GTFOBins’ notes, from GTFOBins, at commit acd524623f9c of 2026-05-27, under the GPL-3.0, with no warranty. Changed: Markdown is shown formatted. The source is in lolbas-gtfobins-commands.json.gz, and the full entry is on GTFOBins’s page for strace. The identifier reads the line of each that runs strace.
What detects it
Everyday use
Start tracing a specific process by its PID
sudo strace --attach process_idIdentifyTrace a process and filter output by system call expression
sudo strace --attach process_id -e system_call,system_call2,...IdentifyCount time, calls, and errors for each system call and report a summary on program exit
sudo strace --attach process_id --summary-onlyIdentifyNone of the 3 examples the identifier reads matches GTFOBins abuse or trips a Sigma process-creation rule.