zlibsrcPyPI
Malicious code in zlibsrc (PyPI) Remove it immediately and rotate any exposed credentials.
What this malware does
Security researchers at Check Point Research discovered a malicious package called zlibsrc impersonating the PyPI package zlib. PyPI has since removed zlibsrc.
Malicious versions
Every published version of this package is considered malicious — remove it entirely.
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 zlibsrc (all published versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging zlibsrc across your stack and pipelines.
If you installed it — respond
zlibsrc is a typosquat — you almost certainly intended a legitimately-named package. Remove zlibsrc, 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 zlibsrc 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 zlibsrc 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
Detect & block this
O3 blocks zlibsrc-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.