loadtest-browser-libnpm
Malicious code in loadtest-browser-lib (npm) Remove it immediately and rotate any exposed credentials.
What this malware does
On npm install, the package's preinstall hook executes index.js, which collects host identifiers (hostname, username, platform, arch, cwd, pid, timestamp) and sends them as query parameters in an HTTPS request to fxpkkxatijbbyxuhdclqig6334q9m1j8w.oast.fun, an out-of-band callback host. package.json declares "preinstall": "node index.js", so the beacon fires automatically on default install with no user interaction. The package self-describes as 'hijacking by yusif', consistent with a dependency-confusion / namespace-hijack proof-of-concept payload. Any installer running npm install leaks identifying machine information to the attacker's collaborator endpoint.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Backdoor / remote accessFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for loadtest-browser-lib (version 1.31.3). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging loadtest-browser-lib across your stack and pipelines.
If you installed it — respond
loadtest-browser-lib establishes remote access, so treat any host that installed it as fully compromised. Isolate the machine, remove the package, rotate all credentials it could reach, and rebuild from a trusted image rather than cleaning in place — a backdoor may have planted additional persistence.
Did it already run?
If loadtest-browser-lib 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 loadtest-browser-lib 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 loadtest-browser-lib-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.