Which versions of base65-77x are malicious?

The following npm versions of base65-77x are flagged malicious: 5.0.2. Treat any of these as compromised.

How do I remediate base65-77x if I installed it?

base65-77x 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 base65-77x — how do I know if it already compromised me?

If base65-77x 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 base65-77x part of a known attack campaign?

Yes — base65-77x is associated with the IN-MAL-2026-017383 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 base65-77x across my projects, lockfiles, and CI pipelines?

Search your lockfiles and build artifacts for base65-77x (version 5.0.2).

Malicious package

base65-77xnpm

Advisory published Aug 11, 2026Updated Aug 11, 2026

base65-77x is a confirmed malicious npm package (MAL-2026-13750) 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 base65-77x (npm)

MAL-2026-13750

Immediate action

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

npm uninstall base65-77x

What this malware does

The package impersonates base-x (name, description, keywords, and homepage copied from base-x) and patches the advertised decode() function in both the CommonJS and ESM entrypoints to POST the caller-supplied input string to a hardcoded remote destination at http://46.250.253.63:3000/api/log over plain HTTP before returning the decoded result. Because base-x is commonly used to decode base58/base64 material such as wallet addresses, private keys, seeds, and tokens, any string passed to decode() is silently forwarded to the hardcoded bare-IP endpoint, which is not first-party and not caller-configurable.

Malicious versions

1 flagged

5.0.2

Indicators of compromise (SHA-256)

ef76e83f2641fcfacf488a6ef61447fac81f6a24cff6287b407a385374b9ddf7

Detection & response playbook

Credential / info stealer

Find it
Search your lockfiles and build artifacts for base65-77x (version 5.0.2).
If you installed it — respond
base65-77x 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 base65-77x 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. base65-77x 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-2026-017383

References

npmjs.com

Credits

Amazon Inspector · finder

Detect & block this

O3 blocks base65-77x-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

All malware advisories How O3 detects malware Vulnerability database