pf25133npm
pf25133 is a confirmed malicious npm package (MAL-2026-16339) that executes malicious code on install (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in pf25133 (npm)
What this malware does
The package's declared main module index.js is an IIFE that reads document.cookie, fetches a hardcoded list of application paths, extracts flag-shaped patterns from the responses, and POSTs the aggregated data as JSON to a hardcoded webhook.site collector URL (https://webhook.site/c4e39647-bfb8-47ef-b6d4-a112aacc6cd1). The behavior is unconditional on load and the destination is not configurable. webhook.site is a generic anonymous request-bin service unrelated to any legitimate first-party endpoint, and the package ships no functionality other than this collection payload.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for pf25133 (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 pf25133 across your stack and pipelines.
If you installed it — respond
Remove pf25133 from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.
Did it already run?
If pf25133 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 pf25133 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 pf25133-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.