MalwarePublished 11 Aug 2026Updated 12 Nov 2026

base65-77x (npm) · Malicious Code

Affects base65-77xSource GCVE Database

Malicious package : remove base65-77x and rotate any secrets on hosts that installed it.

Data as of 12 Nov 2026, 20:41 UTC

Classification

Malicious package

Published to npm · OSV MAL-2026-13750

What to do

Remove base65-77x from every project, lockfile and image that pulls it in. Treat any host that installed it as compromised: rotate the credentials, tokens and keys it could read, from a clean machine.

Affected software

Product	Affected	Fixed in
npmbase65-77x	Affected =5.0.2	Fixed in–

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Description

The npm package base65-77x impersonates the legitimate base-x package and contains malicious code that exfiltrates input data passed to its decode() function to a remote server. This package silently sends potentially sensitive data such as wallet addresses, private keys, seeds, and tokens to an attacker-controlled endpoint before returning the decoded result. Installation or use of this package compromises the host system, and all secrets on the affected system should be considered exposed and rotated immediately.

Impact

Any secrets or keys decoded using this package are silently transmitted to an attacker-controlled server, leading to potential theft of sensitive cryptographic material. Systems with this package installed are considered fully compromised, with attackers potentially having full control. This can result in loss of funds, identity theft, or unauthorized access to protected resources.

Defensive guidance

Remove the base65-77x package immediately from all affected systems. Rotate all secrets, keys, and tokens that may have been exposed, using a secure and uncompromised environment. Because the package grants attackers potential full control over the system, consider a full security audit and system rebuild to ensure no persistent backdoors remain.

Summary

The malicious npm package base65-77x mimics the legitimate base-x package by copying its name, description, keywords, and homepage. It modifies the decode() function in both CommonJS and ESM entrypoints to send the caller-supplied input string to a hardcoded remote HTTP endpoint (http://46.250.253.63:3000/api/log) before returning the decoded output. Since base-x is commonly used to decode sensitive base58/base64 data such as cryptocurrency wallet addresses, private keys, seeds, and tokens, this exfiltration can lead to full compromise of secrets. The package is identified as malware, and any system with it installed should be treated as fully compromised.

References

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What to do

Affected software

Description

AI analysisMachine-generated, updated 12 Nov 2026, 20:41 UTC

Technical details

References

Community reviews