MAL-2026-17795 Malicious code in sol-mint-utils (RubyGems)

The gem ships a native-extension stub (extconf.rb) that gem install executes automatically, but no C/C++ sources accompany it and lib/sol_mint_utils.rb is an inert stub (defines VERSION and returns 'ok'). The README advertises an unrelated package name (bitcoin-rpc-lite), confirming the gem's declared purpose is a cover. extconf.rb base64-decodes a Ruby payload and eval's it inside a forked/detached process; the decoded payload opens a TCPSocket to the hardcoded host 45.138.12.177 on port 8089 and bridges a /bin/sh session over the socket via IO.popen and IO.copy_stream, granting the operator an interactive reverse shell on the installer's machine. Execution is gated by anti-analysis checks: CI environment variables, hostname patterns (uvm/firecracker/sandbox/vagrant), generated usernames, analysis working directories (/opt/rubygems, /tmp, /workspace), and short /proc/uptime values all suppress the payload, which fires only when developer artifacts such as ~/.ssh, ~/.gitconfig, and ~/.gem/credentials are present on the host.

The OpenSSF Package Analysis project identified 'sol-mint-utils' @ 0.9.1 (rubygems) as malicious.

It is considered malicious because:

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