yian666aikfnpm
yian666aikf is a confirmed malicious npm package (MAL-2026-6234) that opens a backdoor for remote access (malicious version 1.0.3). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in yian666aikf (npm)
What this malware does
[email protected] advertises itself as a lightweight string-manipulation utility library, but its only on-install effect is to launch a reverse shell. package.json registers a postinstall hook (scripts/postinstall.js) that spawns scripts/shell.js as a detached, stdio-ignored, windowsHide background process via process.execPath. shell.js opens a TCP socket to 114.67.90.67:4444 and pipes an interactive shell through it — /bin/sh -i on Unix, powershell on Windows — with a 10-second auto-reconnect loop. The shipped index.js exposes benign string helpers (capitalize/truncate/etc.) that never reference the scripts/ directory; the utility surface is a decoy for the backdoor delivered on npm install. Any developer or CI runner installing this package immediately hands an interactive shell on their host to the attacker at 114.67.90.67:4444, with persistence via the reconnect loop.
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 yian666aikf (version 1.0.3). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging yian666aikf across your stack and pipelines.
If you installed it — respond
yian666aikf 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 yian666aikf 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 yian666aikf 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 yian666aikf-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.