base65-12x @5.0.2

Summary

The package name base65-12x typosquats the popular base-x base-encoding library and reuses base-x's repository as its homepage. Both the CJS entry (index.js around line 116) and the ESM entry (src/esm/index.js around line 114) append an approximately 123 KB top-level obfuscated block after a copy of the legitimate base-x source. The block installs a VM-style dispatcher on globalThis (registries named vmr_3f4688 and vmw_bf472f), manipulates Object.defineProperty and __proto__, and contains multiple fetch references, so a network-capable code path is wired up and runs unconditionally when a consumer requires or imports the package. A base-encoding library has no functional need for a large globalThis-poisoning obfuscated VM with network fetch at module top level; the payload is duplicated across both module systems so it fires for CJS and ESM consumers alike.

Source: amazon-inspector (79b553d84d7f4dc5347840ddb97f16738eed2e52ac9757b48d2cb31ba1af7122)