Which versions of express-configer are malicious?

The following npm versions of express-configer are flagged malicious: 2.4.1, 2.4.2, 2.4.3. Treat any of these as compromised.

How do I remediate express-configer if I installed it?

Remove express-configer 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 express-configer — how do I know if it already compromised me?

If express-configer 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 express-configer part of a known attack campaign?

Yes — express-configer is associated with the GHSA-69cq-35c9-qwg9, RLMA-2026-01303 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 express-configer 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 express-configer (3 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging express-configer across your stack and pipelines.

Malicious package

express-configernpm

Malicious code in express-configer (npm) Remove it immediately and rotate any exposed credentials.

MAL-2026-833

Immediate action

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

npm uninstall express-configer

What this malware does

The package express-configer was found to contain malicious code.

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

3 flagged

2.4.12.4.22.4.3

Indicators of compromise (SHA-256)

8484436a0b43b94054c0fa7ceb955362a6557d9bef3019e2fae2e51e42ff1f7b

e492b9087ab21198777e586b9d21eade1fe2948bb67f1ab484c7274056861276

cf6fac0500036f57fe926c31290bbb2437d550d315b07189ba1092155a368663

Detection & response playbook

Malicious package

Find it
Scan your lockfiles (package-lock.json, pnpm-lock.yaml, yarn.lock, requirements.txt, poetry.lock, etc.) and build artifacts for express-configer (3 malicious versions). O3 Security's supply-chain scanner checks every dependency against known-malicious package intelligence at install time and in CI, flagging express-configer across your stack and pipelines.
If you installed it — respond
Remove express-configer 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 express-configer 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 express-configer 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. express-configer on npm has been identified as a malicious package (versions 2.4.1, 2.4.2, 2.4.3 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

GHSA-69cq-35c9-qwg9RLMA-2026-01303

References

github.com

Credits

Amazon Inspector · finder
ReversingLabs · finder

Detect & block this

O3 blocks express-configer-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