http-ws-listenernpm
Advisory published Updated
http-ws-listener is a confirmed malicious npm package (MAL-2026-10623) that opens a backdoor for remote access (malicious version 1.0.5). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in http-ws-listener (npm)
What this malware does
[email protected] ships misc/configFetcher.js, which reconstructs a hidden Pastebin URL and the module names 'net' and 'child_process' by triple-base64-decoding a Lorem-ipsum string literal and indexing characters through a numeric array. When the package's advertised entrypoint startWebSocketServer() is called, fetchConfig() retrieves colon-separated handles from the paste, dynamically imports the built-in net and child_process modules, invokes child_process.exec on a second remote-fetched string, opens a TCP socket to a host:port also carried in the paste, and pipes that socket into the child process's stdin, stdout, and stderr. The result is an interactive reverse shell on the machine running the package, driven by content that the paste author can mutate at any time. The obfuscation (triple base64 plus character-index reconstruction) exists to hide the C2 URL and the built-in module names from static inspection.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Backdoor / remote accessFind it
Search your lockfiles and build artifacts for http-ws-listener (version 1.0.5).
If you installed it — respond
http-ws-listener 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 http-ws-listener was installed, its post-install payload may already have run. Removing the package does not undo that — check outbound connections and credential use from the install window onward.
Frequently asked questions
Campaign
References
Credits
- Amazon Inspector · finder
Detect & block this
O3 blocks http-ws-listener-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.