Which versions of formatters.ts are malicious?

The following npm versions of formatters.ts are flagged malicious: 14.2.1. Treat any of these as compromised.

How do I remediate formatters.ts if I installed it?

formatters.ts 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.

I already installed formatters.ts — how do I know if it already compromised me?

If formatters.ts 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.

Is formatters.ts part of a known attack campaign?

Yes — formatters.ts is associated with the IN-MAL-2026-010679 campaign. Packages in the same campaign often share infrastructure and payloads, so check whether any related packages are also in your dependency tree.

How do I find formatters.ts across my projects, lockfiles, and CI pipelines?

Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for formatters.ts (version 14.2.1). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging formatters.ts across your stack and pipelines.

Malicious package

formatters.tsnpm

Malicious code in formatters.ts (npm) Remove it immediately and rotate any exposed credentials.

MAL-2026-10683

Immediate action

Remove the package, then rotate any secrets the build/runtime could reach.

npm uninstall formatters.ts

What this malware does

The package declares a preinstall hook that runs index.js on npm install. index.js collects host and identity reconnaissance — os.hostname(), os.platform(), os.arch(), os.homedir(), os.userInfo() (username, uid, gid, shell), OS release, memory, CPU count, and the output of the whoami, id, and pwd shell commands — and POSTs the JSON payload to a hardcoded Burp Collaborator subdomain at https://y43nklho48nnebq8qpmw3ngha8gz4pse.oastify.com/detox56. The package name resembles a legitimate formatter/TypeScript module and ships with empty description/author metadata, consistent with a dependency-confusion typosquat lure whose sole purpose is the install-time beacon.

Malicious versions

1 flagged

14.2.1

Indicators of compromise (SHA-256)

21827129edc8dbde114c615df656d5a234d1fbcfa5b9f63d5286d781253e8f2b

Detection & response playbook

Backdoor / remote access

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for formatters.ts (version 14.2.1). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging formatters.ts across your stack and pipelines.
If you installed it — respond
formatters.ts 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 formatters.ts 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 formatters.ts 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

No. formatters.ts on npm has been identified as a malicious package (version 14.2.1 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-010679

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks formatters.ts-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the C2 callback and severs the channel.

Malware detection Runtime egress monitoring