Which versions of modern-localization are malicious?

The following npm versions of modern-localization are flagged malicious: 1.1.1, 1.2.1. Treat any of these as compromised.

How do I remediate modern-localization if I installed it?

Remove modern-localization from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.

I already installed modern-localization — how do I know if it already compromised me?

If modern-localization 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 modern-localization part of a known attack campaign?

Yes — modern-localization is associated with the IN-MAL-2026-017194, IN-MAL-2026-017201 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 modern-localization across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for modern-localization (2 malicious versions).

Malicious package

modern-localizationnpm

Advisory published Aug 8, 2026Updated Aug 8, 2026

modern-localization is a confirmed malicious npm package (MAL-2026-13633) that executes malicious code on install (malicious versions 1.1.1, 1.2.1). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in modern-localization (npm)

MAL-2026-13633

Immediate action

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

npm uninstall modern-localization

What this malware does

On server-side require of modern-localization, the package's main entry runs a top-level async IIFE (syncLanguageSystem) that performs an HTTP GET against a hardcoded jsonbin.io endpoint (https://api.jsonbin.io/v3/b/6a764665da38895dfec7cd5d and https://api.jsonbin.io/v3/b/6a718a58da38895dfeb6e2ed) and executes the returned string as JavaScript with full Node privileges. utils.js passes the fetched record.value into new Function('require', payload) invoked with the real require reference; index.js writes the fetched payload to a temp file and invokes it via child_process.fork. The destination is a third-party mutable key-value store whose contents are controlled by whoever owns the bin, and there is no pinning, hash check, or signature verification. The channel is framed by identifier and log naming ('syncLanguageSystem', 'lang_source', 'LANG_PASS_KEY') as a language synchronization feature, but a localization library has no legitimate need to fetch and execute arbitrary JavaScript; translations are static data.

Malicious versions

2 flagged

1.1.11.2.1

Indicators of compromise (SHA-256)

fb8c3ecffe571be82855309d66a7e825cda13b98d046060c915e6c8e0dd0d70e

4be23667d11e7ef3357641973b9188175c2068bd2b580a5628773bcdf03533a5

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for modern-localization (2 malicious versions).
If you installed it — respond
Remove modern-localization from your project and lockfile, then assume any secrets accessible to the build or runtime were exposed: rotate API keys, tokens, and credentials, and audit for unexpected outbound activity or persistence.
Did it already run?
If modern-localization 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. modern-localization on npm has been identified as a malicious package (versions 1.1.1, 1.2.1 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-017194IN-MAL-2026-017201

References

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks modern-localization-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the malicious outbound activity and severs the channel.

Malware detection Runtime egress monitoring

Explore

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