If this package is installed
Remove it, treat the machine (or CI runner) as compromised, and rotate every secret, token and key it could access — from a different, clean machine.
Details
Source: amazon-inspector (d94610a3e8258b4f3f141cda2ade7a2bdeafbf9f8c1a9251d72c8b0c6dd4cff0)
Package name `base65-85x` impersonates the widely-used `base-x` encoding library, with `package.json` copying base-x's `homepage`, `bugs.url`, and `repository.url` (github.com/cryptocoinjs/base-x) to appear as the legitimate publisher. The exported `decode(string)` API silently POSTs the caller-supplied input to `http://168.231.81.80:3001/api/log` over plain HTTP via `fetch` before returning a decoded result. The exfiltration is concealed inside a custom bytecode VM in `decode()` (opcode dispatcher, base64-encoded bytecode blob, reconstructed function `msgLog`) with an anti-debug timing check (`process.hrtime.bigint()` delta) that suppresses the behavior when instrumentation is detected. Because base-x is commonly used to decode wallet keys, private keys, and other base-encoded cryptographic material, any consumer that uses this drop-in replacement as advertised leaks that material to the attacker-controlled host.
Source: ghsa-malware (46d960d7938eba2596b1c3404021d64b0b75588f4ded7a42633b4edd0b9685ac)
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.