insomnia-plugin-poc-m4gester-runnpm
insomnia-plugin-poc-m4gester-run is a confirmed malicious npm package (MAL-2026-10493) that typosquats a legitimate package to trick installs (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in insomnia-plugin-poc-m4gester-run (npm)
What this malware does
package.json declares a postinstall lifecycle hook that runs calc.exe on the installer's machine during npm install. The main entry point exports only an empty requestHooks array, providing no actual Insomnia plugin functionality — the package's sole effect is the arbitrary command execution at install time. The name self-identifies as a proof-of-concept and mimics the Insomnia plugin naming convention with a leet-substituted variant, indicating the package exists solely to demonstrate/exploit install-time RCE. While calc.exe itself is benign, the postinstall hook establishes full arbitrary-command-execution capability against any developer installing the package on Windows.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
TyposquatFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for insomnia-plugin-poc-m4gester-run (version 1.0.0). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging insomnia-plugin-poc-m4gester-run across your stack and pipelines.
If you installed it — respond
insomnia-plugin-poc-m4gester-run is a typosquat — you almost certainly intended a legitimately-named package. Remove insomnia-plugin-poc-m4gester-run, install the correct package, and rotate any secrets exposed during the install since post-install scripts may have already run.
Did it already run?
If insomnia-plugin-poc-m4gester-run was ever installed, its post-install/runtime payload may have already executed. O3's L7 egress monitoring and runtime eBPF sensors detect the credential exfiltration or command-and-control callback after install and block the malicious outbound channel, so you catch and contain the actual compromise — not just the presence of the package.
How O3 protects you
O3 blocks insomnia-plugin-poc-m4gester-run before install through its supply-chain scanner, and if it has already run, detects and severs the exfiltration or C2 callback at runtime through L7 egress monitoring and eBPF.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks insomnia-plugin-poc-m4gester-run-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.