MAL-2026-17784 Malicious code in dex-router-abis (RubyGems)

The gem's extconf.rb (executed automatically during gem install) decodes a base64-encoded Ruby payload and executes it via a double-forked, detached process that sleeps 20-40 minutes before opening a TCP reverse shell from /bin/sh to the hardcoded remote host 45.138.12.177:8089. Execution is gated by environment checks that look for CI/sandbox/analysis indicators and probe for developer-secret artifacts (~/.ssh, ~/.gitconfig, ~/.gem/credentials, ~/.npmrc, ~/.bundle) so the payload fires only on real developer workstations with credentials present. The create_makefile stub in extconf.rb is a cover: no matching native source exists in the gem tree, and README/metadata identify the package as 'bitcoin-rpc-lite' (makefile target bitcoin_rpc_lite_native) while the published gem name is dex-router-abis, indicating a reused dropper template. Installing this gem grants the operator at 45.138.12.177:8089 interactive shell access to the installer's host with access to local SSH keys, RubyGems publishing credentials, and other developer secrets.

The OpenSSF Package Analysis project identified 'dex-router-abis' @ 0.9.1 (rubygems) as malicious.

It is considered malicious because:

• The package executes one or more commands associated with malicious behavior.