---
id: "MAL-2026-18378"
kind: "package"
aliases: ["MAL-2026-18378"]
title: "Malicious code in poc-revshell (PyPI)"
severity: "critical"
cvss: null
epss: null
exploited: false
status: "open"
category: "package"
products: [{"name": "poc-revshell", "fixed": [], "affected": "= 0.1.0", "ecosystem": "pypi"}]
ecosystems: ["pypi"]
tags: ["malicious", "package"]
not_affected_if: []
published_at: "2026-10-29T14:59:05+00:00"
first_seen_at: "2026-10-29T15:54:55+00:00"
updated_at: "2026-10-29T18:39:09+00:00"
sources: [{"source": "osv-malicious", "url": "https://osv.dev/vulnerability/MAL-2026-18378", "first_seen_at": "2026-10-29T15:54:55+00:00"}]
---

# Malicious code in poc-revshell (PyPI)

## Affected

- pypi:poc-revshell affected = 0.1.0 fixed ?

## Timeline

- 2026-10-29T15:54:55+00:00 osv-malicious https://osv.dev/vulnerability/MAL-2026-18378

## From the sources

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_-= Per source details. Do not edit below this line.=-_

## Source: amazon-inspector (08edc162927c80cde9e467244a435780f65ca95823e97ec73534faf34233ac9a)
poc-revshell 0.1.0 ships a reverse-shell backdoor that fires both at install time and at import time. setup.py registers a custom `install` cmdclass (PostInstall) that starts a daemon thread executing a routine which opens a TCP socket to 127.0.0.1:4444, dup2s the socket file descriptor onto stdin/stdout/stderr, and execs `/bin/sh -i` (or `cmd.exe` on Windows); this runs automatically during `pip install`. The package's `__init__.py` contains the same thread-launch at module top level, so every `import poc_revshell` repeats the handoff. Any local listener on port 4444 at the moment of install or import receives a full interactive shell running under the installing user's identity. The destination is hardcoded loopback, which confines the attack to a co-resident attacker on the installer's host, but the install-time and import-time network-to-shell dataflow is a backdoor by structure, matching the package's self-description as a proof-of-concept that triggers a reverse shell on pip install.

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