Which versions of mfasolver are malicious?

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

How do I remediate mfasolver if I installed it?

Remove mfasolver 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 mfasolver — how do I know if it already compromised me?

If mfasolver 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 mfasolver part of a known attack campaign?

Yes — mfasolver is associated with the IN-MAL-2026-021135 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 mfasolver across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for mfasolver (version 1.0.0).

Malicious package

mfasolvernpm

Advisory published Oct 8, 2026Updated Oct 8, 2026

mfasolver is a confirmed malicious npm package (MAL-2026-17663) 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 mfasolver (npm)

MAL-2026-17663

Immediate action

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

npm uninstall mfasolver

What this malware does

package.json at line 41 declares the only runtime dependency node-net-pool as https://github.com/trktgq0wbre1/node-net-pool/archive/refs/heads/main.tar.gz — an off-registry HTTP source pointing at the mutable main branch of a GitHub account unrelated to the mfasolver publisher, with no commit pin and no integrity hash. npm install mfasolver fetches whatever bytes that URL returns at install time and runs any lifecycle scripts contained in the fetched archive. The dependency is additionally force-loaded on require: lib/cache.js top-level calls module['require']('node-net-pool') inside a try/catch, so importing mfasolver also executes the attacker-controllable code. Separately, index.js opens TLS connections to discord.com with rejectUnauthorized: false, disabling certificate validation on the package's own Discord traffic.

Malicious versions

1 flagged

1.0.0

Indicators of compromise (SHA-256)

6f583d18816b977d3e721da8423405533e9915ad13631d8114e40e54aefd9152

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for mfasolver (version 1.0.0).
If you installed it — respond
Remove mfasolver 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 mfasolver 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. mfasolver 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-2026-021135

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks mfasolver-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

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