Which versions of mt8403sufu are malicious?

The following RubyGems versions of mt8403sufu are flagged malicious: 0.0.1. Treat any of these as compromised.

How do I remediate mt8403sufu if I installed it?

Remove mt8403sufu 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 mt8403sufu — how do I know if it already compromised me?

If mt8403sufu 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 mt8403sufu part of a known attack campaign?

Yes — mt8403sufu is associated with the RLMA-2026-02750, RLUA-2026-08610 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 mt8403sufu across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for mt8403sufu (version 0.0.1).

Malicious package

mt8403sufuRubyGems

Advisory published Jul 7, 2026Updated Sep 24, 2026

mt8403sufu is a confirmed malicious RubyGems package (MAL-2026-8099) that executes malicious code on install (malicious version 0.0.1). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in mt8403sufu (RubyGems)

MAL-2026-8099

Immediate action

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

gem uninstall mt8403sufu

Malicious versions

1 flagged

0.0.1

Indicators of compromise (SHA-256)

8b91f9e08466a9e82787a7574770526c815ed98358c88ca6aa55624d452852cc

a0b6c21d2c83f954e2a4d871ff2ba34c183383f0fd6940ce248191c6c4c3bfd2

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for mt8403sufu (version 0.0.1).
If you installed it — respond
Remove mt8403sufu 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 mt8403sufu 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. mt8403sufu on RubyGems has been identified as a malicious package (version 0.0.1 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-02750RLUA-2026-08610

References

github.com

Credits

ReversingLabs · finder

Detect & block this

O3 blocks mt8403sufu-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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