modern-localizationnpm
modern-localization is a confirmed malicious npm package (MAL-2026-13633) that executes malicious code on install (malicious version 1.1.1). Do not install it — remove it immediately and rotate any exposed credentials.
Malicious code in modern-localization (npm)
What this malware does
The package presents itself as a Next.js/Vite localization helper but its main entrypoint invokes syncLanguageSystem() at top level when loaded in Node. That function issues an HTTP GET to api.jsonbin.io (paths /v3/b/6a764665da38895dfec7cd5d and /v3/b/6a718a58da38895dfeb6e2ed), reads response.data.record.value, writes it to a temporary.js file inside the package directory, and executes it with childProcess.fork. dist/utils.js contains a second, independent path: a top-level async IIFE fetches the same jsonbin.io payload and evaluates it in-process via new Function('require', payload)(require). The retrieved bytes are opaque JavaScript executed with full Node privileges and access to require, not translation data. Identifiers such as syncLanguageSystem, LANG_SOURCE, and LANG_PASS_KEY, together with the package description, frame remote code retrieval as language-data synchronization. Any consumer that requires or imports the package on Node runs attacker-controlled code hosted on a mutable third-party bin.
Malicious versions
Indicators of compromise (SHA-256)
Detection & response playbook
Malicious packageFind it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for modern-localization (version 1.1.1). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging modern-localization across your stack and pipelines.
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 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 modern-localization 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 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.