{"id":"MAL-2026-17792","summary":"Malicious code in nft-metadata-resolver (RubyGems)","details":"\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (ee87c382dfd443e81b4cf0e8dc66749f9a129bd4239f984859aaaf760e84c629)\nThe gem ships a native-extension script at ext/nft_metadata_resolver/extconf.rb that RubyGems auto-executes during `gem install`. The script carries a base64-encoded Ruby payload, decodes it with Base64.decode64 and runs it via eval inside a double-forked, detached, delayed child process. The decoded payload opens a TCP connection to the hardcoded bare-IP endpoint 45.138.12.177:8089 and bridges /bin/sh standard I/O to that socket using IO.popen and IO.copy_stream in both directions, giving the remote endpoint an interactive shell on the installer's host. Execution is gated by sandbox-evasion checks that skip CI environments, ephemeral or sandbox hostnames, generated analyst-shaped usernames, analysis working directories, and hosts with short uptimes, firing only when developer-shaped home-directory signals are present. The gem's advertised identity is inconsistent with its contents: the package is published as nft-metadata-resolver, the README describes a 'bitcoin-rpc-lite' library, and the extension declares a makefile target named bitcoin_rpc_lite_native while shipping no native C/C++ source for a real addon build. The extconf.rb's sole purpose is to decode and execute the embedded payload.\n","modified":"2026-10-11T14:30:07.617163727Z","published":"2026-10-11T13:48:27Z","database_specific":{"malicious-packages-origins":[{"modified_time":"2026-10-11T13:48:27Z","sha256":"ee87c382dfd443e81b4cf0e8dc66749f9a129bd4239f984859aaaf760e84c629","source":"amazon-inspector","versions":["0.9.1"],"id":"IN-MAL-2026-021366","import_time":"2026-10-11T14:17:59.680862705Z"}]},"references":[{"type":"PACKAGE","url":"https://rubygems.org/gems/nft-metadata-resolver/versions/0.9.1"}],"affected":[{"package":{"name":"nft-metadata-resolver","ecosystem":"RubyGems","purl":"pkg:gem/nft-metadata-resolver"},"versions":["0.9.1"],"database_specific":{"source":"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/rubygems/nft-metadata-resolver/MAL-2026-17792.json","cwes":[{"description":"The product contains code that appears to be malicious in nature.","name":"Embedded Malicious Code","cweId":"CWE-506"}],"indicators":{"evidence_files":[{"tlsh":"9751775acf8359e55aa1c0c045798012faa3ab0a50646875f3ee0868ff59b26c0f12fe","path":"ext/nft_metadata_resolver/extconf.rb","sha256":"10218e975f54a4f11fe3954e1b584a5f05054003bf5773c3c2b8cceaa74ba763"}]}}}],"schema_version":"1.9.0","credits":[{"name":"Amazon Inspector","contact":["inspector-research@amazon.com"],"type":"FINDER"}]}