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 (5710eb2e1a2f6b7a4aca8d943953989e80e056cc77c2071027c2a78744b5ea3a)
chat-adapter-matrix@99.99.99 executes server.js from every npm lifecycle hook (preinstall, install, postinstall, prepare, prepublish, preprepare, postprepare) and from the main module. server.js issues an HTTPS GET to the hardcoded webhook host eo8f3m3ho26a0nm.m.pipedream.net with the package name embedded in the URL path (https://eo8f3m3ho26a0nm.m.pipedream.net/vercel/<pkg>). The receiving Pipedream endpoint captures the source IP, hostname context, and confirmation that this squatted name was resolved and installed. The implausibly high 99.99.99 version and the embedded 'Proof by @0xWise' string are consistent with a dependency-confusion payload designed to win version resolution against an internal package of the same name and beacon successful installs on internal build systems to the researcher/attacker's collector.