Which versions of base65-33x are malicious?

The following npm versions of base65-33x are flagged malicious: 5.0.2. Treat any of these as compromised.

How do I remediate base65-33x if I installed it?

base65-33x is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.

I already installed base65-33x — how do I know if it already compromised me?

If base65-33x 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 base65-33x part of a known attack campaign?

Yes — base65-33x is associated with the IN-MAL-2026-017382 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 base65-33x across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for base65-33x (version 5.0.2).

Malicious package

base65-33xnpm

Advisory published Aug 11, 2026Updated Aug 11, 2026

base65-33x is a confirmed malicious npm package (MAL-2026-13749) that steals credentials and exfiltrates sensitive data (malicious version 5.0.2). Do not install it — remove it immediately and rotate any exposed credentials.

Malicious code in base65-33x (npm)

MAL-2026-13749

Immediate action

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

npm uninstall base65-33x

What this malware does

Package name resembles the popular base-x encoder/decoder. The exported decode(string) function in both CJS and ESM entrypoints POSTs its caller-supplied input to the hardcoded bare-IP endpoint http://168.231.81.80:3002/api/log over plain HTTP on every invocation before returning the decoded buffer. Because base-x-style decoders are commonly used on wallet keys, Base58 Bitcoin material, and other cryptographic secrets, any secret passed to decode() is silently relayed to an attacker-controlled host. Both require and import consumers trigger the same relay path.

Malicious versions

1 flagged

5.0.2

Indicators of compromise (SHA-256)

f4e22e29bf42b32b80c5336d5f38d10d96879c84f162d86565289b588253589b

Detection & response playbook

Credential / info stealer

Find it
Search your lockfiles and build artifacts for base65-33x (version 5.0.2).
If you installed it — respond
base65-33x is built to steal secrets, so assume every credential the build or runtime could read is compromised. Remove it from your project and lockfile, then rotate ALL exposed secrets — npm/registry tokens, cloud keys, CI/CD secrets, SSH keys, and any .env values — from a known-clean machine. Audit logs for unauthorized use of those credentials.
Did it already run?
If base65-33x 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. base65-33x on npm has been identified as a malicious package (version 5.0.2 flagged). It should be removed immediately — do not install or keep it in your dependency tree.

Campaign

IN-MAL-2026-017382

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks base65-33x-class packages before install and in CI — and if it already ran, its runtime egress monitoring catches the credential exfiltration and severs the channel.

Malware detection Runtime egress monitoring

Explore

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