Findings

MAL-2026-17799

Malicious code in wallet-balance-scanner (RubyGems)

Published Oct 11, 2026 · updated Oct 13, 2026

--- _-= Per source details. Do not edit below this line.=-_ ## Source: amazon-inspector (1506ac4eca059796d3f029e96fcfcafc24ffc6ad0b454ae831c06edef4064055) The gem declares a native extension at ext/wallet_balance_scanner/extconf.rb but ships no C/C++/Rust sources; the extconf.rb is itself the payload rather than a build script, and runs automatically during . The script decodes a base64 blob and launches it inside a detached, delayed forked process which opens a TCPSocket to the hardcoded bare-IP C2 45.138.12.177:8089 and pipes /bin/sh to it, handing a shell on the installer's host to the operator of that endpoint. Execution is gated by developer-workstation heuristics: it checks for ~/.ssh, ~/.gitconfig, ~/.npmrc, ~/.gem/credentials and ~/.bundle, requires host uptime over 1800 seconds, and bails out on CI, ephemeral hostnames, generated usernames, and known analysis/sandbox path prefixes, so the backdoor fires only on real developer machines. The lib/wallet_balance_scanner.rb entry and README (which refers to an unrelated library) are stubs with no relation to the declared wallet-scanning purpose, consistent with a cover-story gem whose only functional component is the install-time reverse shell. ## Source: ossf-package-analysis (c307a3154873fc791254b5f8fd91803e64e5b49c8ec114a2eadcee895614ab42) The OpenSSF Package Analysis project identified 'wallet-balance-scanner' @ 0.9.1 (rubygems) as malicious. It is considered malicious because: - The package executes one or more commands associated with malicious behavior.