Which versions of mui-option are malicious?

The following npm versions of mui-option are flagged malicious: 1.0.0. Treat any of these as compromised.

How do I remediate mui-option if I installed it?

Remove mui-option 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 mui-option — how do I know if it already compromised me?

If mui-option 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 mui-option part of a known attack campaign?

Yes — mui-option is associated with the IN-MAL-2026-010713 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 mui-option across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for mui-option (version 1.0.0).

Malicious package

mui-optionnpm

Advisory published Jul 16, 2026Updated Jul 16, 2026

mui-option is a confirmed malicious npm package (MAL-2026-10738) that executes malicious code on install (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in mui-option (npm)

MAL-2026-10738

Immediate action

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

npm uninstall mui-option

What this malware does

The sole shipped file index.js is heavily obfuscated with a base64+RC4 string-array decoder that hides all module names, URLs, and method identifiers. On import (main entrypoint), it requires child_process, os, fs, path, crypto and https, issues an https.get to a runtime-decoded URL, splits the response on ':' into an IV and ciphertext, derives a key with crypto.scryptSync, decrypts the payload with crypto.createDecipheriv, writes the decrypted bytes to a file under os.tmpdir(), and executes that file via child_process.exec. The package has no legitimate advertised functionality, its name resembles the MUI ecosystem, and no other code path exists. Any project that requires mui-option triggers execution of attacker-controlled native code on the installer host. The tarball also ships npm_recovery_codes.txt containing five 64-character hex strings matching the format of npm 2FA recovery codes, suggesting a publishing-account compromise.

Malicious versions

1 flagged

1.0.0

Indicators of compromise (SHA-256)

8e1c3ec117eaeedbd4c3f64c2fec97d44e115d400c7e52082b7d6cc28f7c59ec

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for mui-option (version 1.0.0).
If you installed it — respond
Remove mui-option 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 mui-option 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. mui-option on npm has been identified as a malicious package (version 1.0.0 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-010713

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks mui-option-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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