Which versions of express-auth-basic are malicious?

The following npm versions of express-auth-basic are flagged malicious: 1.2.3. Treat any of these as compromised.

How do I remediate express-auth-basic if I installed it?

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

If express-auth-basic 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 express-auth-basic part of a known attack campaign?

Yes — express-auth-basic is associated with the RLMA-2026-01943 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-auth-basic across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for express-auth-basic (version 1.2.3).

Malicious package

express-auth-basicnpm

Advisory published Apr 16, 2026Updated Apr 23, 2026

express-auth-basic is a confirmed malicious npm package (MAL-2026-2759) that executes malicious code on install (malicious version 1.2.3). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in express-auth-basic (npm)

MAL-2026-2759

Immediate action

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

npm uninstall express-auth-basic

What this malware does

The package express-auth-basic was found to contain malicious code.

Malicious versions

1 flagged

1.2.3

Indicators of compromise (SHA-256)

d9816bd322adc64858055f576e3d66a1018b9cf74cc389169d87154c5ed7c72b

1e643f12d60a16d07664d45cf59400356a38f8bb5463f358e1e86e217b88fab5

Detection & response playbook

Malicious package

Find it
Search your lockfiles and build artifacts for express-auth-basic (version 1.2.3).
If you installed it — respond
Remove express-auth-basic 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-auth-basic 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. express-auth-basic on npm has been identified as a malicious package (version 1.2.3 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

RLMA-2026-01943

Credits

Amazon Inspector · finder
ReversingLabs · finder

Detect & block this

O3 blocks express-auth-basic-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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