Which versions of agfossstd21 are malicious?

The following RubyGems versions of agfossstd21 are flagged malicious: 0.0.1. Treat any of these as compromised.

How do I remediate agfossstd21 if I installed it?

Remove agfossstd21 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 agfossstd21 — how do I know if it already compromised me?

If agfossstd21 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 agfossstd21 part of a known attack campaign?

Yes — agfossstd21 is associated with the RLMA-2026-02129 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 agfossstd21 across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for agfossstd21 (version 0.0.1).

Malicious package

agfossstd21RubyGems

Advisory published Jul 7, 2026Updated Jul 23, 2026

agfossstd21 is a confirmed malicious RubyGems package (MAL-2026-7478) 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 agfossstd21 (RubyGems)

MAL-2026-7478

Immediate action

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

gem uninstall agfossstd21

Malicious versions

1 flagged

0.0.1

Indicators of compromise (SHA-256)

7028289d7125c2633995fb6c57c8740e2fa5b944a146ee369dfaa7c88027051a

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for agfossstd21 (version 0.0.1).
If you installed it — respond
Remove agfossstd21 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 agfossstd21 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. agfossstd21 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-2026-02129

Credits

ReversingLabs · finder

Detect & block this

O3 blocks agfossstd21-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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