simple-date-formatter-new-10npm
simple-date-formatter-new-10 is a confirmed malicious npm package (MAL-2026-13697) that opens a backdoor for remote access (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in simple-date-formatter-new-10 (npm)
What this malware does
[email protected] presents itself as a trivial date-formatting utility but ships two attack payloads that fire when npm installs the package. The package.json postinstall script opens an interactive bash reverse shell over /dev/tcp to 124.221.154.135:4444, giving the publisher remote command execution on the installer's host. A bundled postinstall.js reads the installer's ~/.ssh directory and POSTs its contents together with username and platform to https://124.221.154.135/post, the same C2 endpoint. The advertised date-formatting API (index.js exporting formatDate) is a cover story for the reverse-shell and SSH-key-theft payloads.
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 simple-date-formatter-new-10 (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 simple-date-formatter-new-10 across your stack and pipelines.
If you installed it — respond
simple-date-formatter-new-10 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 simple-date-formatter-new-10 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 simple-date-formatter-new-10 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 simple-date-formatter-new-10-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.