Which versions of thundertiger are malicious?

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

How do I remediate thundertiger if I installed it?

thundertiger is a typosquat — you almost certainly intended a legitimately-named package. Remove thundertiger, install the correct package, and rotate any secrets exposed during the install since post-install scripts may have already run.

I already installed thundertiger — how do I know if it already compromised me?

If thundertiger 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.

Is thundertiger part of a known attack campaign?

Yes — thundertiger is associated with the GHSA-j7j3-pvfq-ph94, IN-MAL-2026-017539 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 thundertiger across my projects, lockfiles, and CI pipelines?

Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for thundertiger (version 1.0.0). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging thundertiger across your stack and pipelines.

Malicious package

thundertigernpm

thundertiger is a confirmed malicious npm package (MAL-2026-13834) that typosquats a legitimate package to trick installs (malicious version 1.0.0). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in thundertiger (npm)

MAL-2026-13834

Immediate action

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

npm uninstall thundertiger

What this malware does

The package's only shipped content is a single HTML file that mimics a Cloudflare 'Just a moment...' security challenge. The inline script is obfuscated with an obfuscator.io-style shuffled string-array + hex identifier decoder and anti-debug console overrides. After a 1-second delay it assembles a hostname from split literals ('gin.microc' + 'loud.homes' → login.microcloud.homes), forwards the current URL's query string, and calls window.location.replace to redirect the browser to that external host. package.json declares no lifecycle scripts and main points at HTML rather than a loadable JS module, so installing or requiring the package does not directly execute the payload against a developer's machine — the harm is directed at end users who load the hosted HTML, using the npm registry as a CDN for a phishing kit. This is registry/namespace abuse rather than a direct installer-side attack; recommend human review to confirm and to coordinate takedown with the registry.

Any computer that has this package installed or running should be considered fully compromised. All secrets and keys stored on that computer should be rotated immediately from a different computer. The package should be removed, but as full control of the computer may have been given to an outside entity, there is no guarantee that removing the package will remove all malicious software resulting from installing it.

Malicious versions

1 flagged

1.0.0

Indicators of compromise (SHA-256)

8949118085f656718342b5f139d62699a87b5ad90135fb45b457dd321f3ebd32

b1c287b2a6653cf3abb51d22059dbe433959b3a2445a75f32e27ed029b1e42d7

Detection & response playbook

Typosquat

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for thundertiger (version 1.0.0). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging thundertiger across your stack and pipelines.
If you installed it — respond
thundertiger is a typosquat — you almost certainly intended a legitimately-named package. Remove thundertiger, install the correct package, and rotate any secrets exposed during the install since post-install scripts may have already run.
Did it already run?
If thundertiger 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 thundertiger 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

No. thundertiger 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

GHSA-j7j3-pvfq-ph94IN-MAL-2026-017539

References

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks thundertiger-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

All malware advisories How O3 detects malware Vulnerability database