CmdID / Programs / Linux and Unix
yarn
JavaScript and Node.js package manager alternative. tldr-pages
GTFOBins shell 1 ATT&CK technique 3 documented commands
How yarn is abused
shell T1059.004 Command and Scripting Interpreter: Unix Shell
exec
shell T1059.004 Command and Scripting Interpreter: Unix Shell
--cwdEach abuse is GTFOBins's category and the options and words it uses; the full write-up is on GTFOBins's page for yarn.
3 documented commands
shell unprivileged, with sudo
yarn exec /bin/shshell unprivileged, with sudo
echo '{"scripts": {"preinstall": "/bin/sh"}}' >package.json
yarn --cwd .shell unprivileged, with sudo
echo '{"scripts": {"xxx": "/bin/sh"}}' >package.json
yarn --cwd . xxxNone of the 3 commands CmdID reads trips a Sigma process-creation rule. These commands are 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 yarn. CmdID reads the line of each that runs yarn.
What detects it
Everyday use
Install a module globally
yarn global add module_nameIdentifyInstall all dependencies referenced in the package.json file (the install is optional)
yarn installIdentifyInstall a module and save it as a dependency to the package.json file (add --dev to save as a dev dependency)
yarn add module_name@versionIdentifyNone of the 3 examples CmdID reads matches GTFOBins abuse or trips a Sigma process-creation rule.