Which versions of formatting-subtitles are malicious?

The following npm versions of formatting-subtitles are flagged malicious: 1.0.2. Treat any of these as compromised.

How do I remediate formatting-subtitles if I installed it?

formatting-subtitles 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 formatting-subtitles — how do I know if it already compromised me?

If formatting-subtitles 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.

Is formatting-subtitles part of a known attack campaign?

Yes — formatting-subtitles is associated with the IN-MAL-2026-021572 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 formatting-subtitles across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for formatting-subtitles (version 1.0.2).

Malicious package

formatting-subtitlesnpm

Advisory published Oct 22, 2026Updated Oct 22, 2026

formatting-subtitles is a confirmed malicious npm package (MAL-2026-18184) that opens a backdoor for remote access (malicious version 1.0.2). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in formatting-subtitles (npm)

MAL-2026-18184

Immediate action

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

npm uninstall formatting-subtitles

What this malware does

package.json declares preinstall: sh./prepare.js && exit 0. prepare.js is shaped like JavaScript (ending with console.log('hello world')) but is executed by /bin/sh, which does not treat /**... */ as a comment. Inside that block, sh evaluates two $(...) command substitutions: one issues a GET to the hardcoded collector https://webhook.site/9e8c8742-3102-4716-aa8b-e150e9e84fe7/stats_1, and the other downloads https://api.github.com/gists/da04f14c93acbe9a7aef827be0a2e91c, extracts a file via jq, writes it to disk as x, and runs it with sh x. On npm install, the installer host fetches and executes arbitrary, unpinned, attacker-controlled content from a mutable GitHub Gist, and the webhook.site beacon discloses the install (and curl-visible metadata such as public IP and user-agent) to the attacker. The JS-comment-wrapping of the shell payload is a deliberate cover story so prepare.js reads as a trivial hello-world when viewed as JavaScript.

Malicious versions

1 flagged

1.0.2

Indicators of compromise (SHA-256)

25577370189f57a5678b2f2c45e212abfc79a3675dc7d51581f633e78aba47a6

Detection & response playbook

Backdoor / remote access

Find it
Search your lockfiles and build artifacts for formatting-subtitles (version 1.0.2).
If you installed it — respond
formatting-subtitles 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 formatting-subtitles 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

No. formatting-subtitles on npm has been identified as a malicious package (version 1.0.2 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-021572

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks formatting-subtitles-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

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