Malicious code in airdrop-eligibility-check (RubyGems)

{
  "id": "b54332771cc9c81f259caf00fb605b74f9e4ae38c82c4e3bb7c2d386982d7c45",
  "url": "https://osv.dev/vulnerability/MAL-2026-17779",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Malicious code in airdrop-eligibility-check (RubyGems)",
    "summary": "--- _-= Per source details. Do not edit below this line.=-_ ## Source: amazon-inspector (eb3461788cd7b809ba613c07b39b583fb968ce927ccfc15433673e2731ca68d8) The gem's extconf.rb, executed during `gem install`, decodes a base64 Ruby payload and eval's it inside a detached double-forked (Process.setsid) child process after a randomized 20–40 minute sleep. The payload opens a TCPSocket to the hardcoded endpoint 45.138.12.177:8089, spawns /bin/sh via IO.popen, and bridges stdio in both directions, providing an interactive reverse shell on the installer's host. Detonation is gated by anti-analysis checks that skip execution in CI, on ephemeral hostnames, under generated usernames, inside analysis paths, and when /proc/uptime is under 1800 seconds; it only arms when developer-credential files are present (~/.ssh, ~/.gitconfig, ~/.gem/credentials, ~/.bundle, ~/.npmrc). The gem has no real functionality: the gemspec name (airdrop-eligibility-check) does not match the README (bitcoin-rpc-lite) or the created makefile (bitcoin_rpc_lite_native), and the lib entry is a trivial stub returning 'ok'. The native-extension build is used solely as a vehicle for the dropper.",
    "evidence": "osv:MAL-2026-17779",
    "products": [
      {
        "name": {
          "value": "airdrop-eligibility-check",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [],
        "affected_versions": [
          {
            "value": "0.9.1",
            "evidence": "/affected/0/versions"
          }
        ]
      }
    ],
    "severity": "unknown",
    "structured": {
      "id": "MAL-2026-17779",
      "aliases": [
        "MAL-2026-17779"
      ],
      "affected": [
        {
          "package": {
            "name": "airdrop-eligibility-check",
            "purl": "pkg:gem/airdrop-eligibility-check",
            "ecosystem": "RubyGems"
          },
          "versions": [
            "0.9.1"
          ],
          "database_specific": {
            "cwes": [
              {
                "name": "Embedded Malicious Code",
                "cweId": "CWE-506",
                "description": "The product contains code that appears to be malicious in nature."
              }
            ],
            "source": "https://github.com/ossf/malicious-packages/blob/main/osv/malicious/rubygems/airdrop-eligibility-check/MAL-2026-17779.json",
            "indicators": {
              "evidence_files": [
                {
                  "path": "ext/airdrop_eligibility_check/extconf.rb",
                  "tlsh": "9751775acf8359e55aa1c0c045798012faa3ab0a50646875f3ee0868ff59b26c0f12fe",
                  "sha256": "10218e975f54a4f11fe3954e1b584a5f05054003bf5773c3c2b8cceaa74ba763"
                },
                {
                  "path": "metadata.yaml",
                  "tlsh": "b321bec0a5c6b476f115d2e7a8503303ab73e90cbf663d016ad78399438817b6747216",
                  "sha256": "e8621dad70ef6c5db1d2d1988a8f35973e9e50900ba3fd0c8217f21db9ca1197"
                }
              ]
            }
          }
        }
      ],
      "modified": "2026-10-11T14:30:07.615744983Z",
      "provider": "osv",
      "references": [
        "https://rubygems.org/gems/airdrop-eligibility-check/versions/0.9.1"
      ],
      "provider_metadata": {
        "malicious-packages-origins": [
          {
            "id": "IN-MAL-2026-021357",
            "sha256": "eb3461788cd7b809ba613c07b39b583fb968ce927ccfc15433673e2731ca68d8",
            "source": "amazon-inspector",
            "versions": [
              "0.9.1"
            ],
            "import_time": "2026-10-11T14:17:58.915504624Z",
            "modified_time": "2026-10-11T13:47:03Z"
          }
        ]
      }
    },
    "related_cves": [],
    "security_relevant": true,
    "severity_evidence": null
  },
  "source_id": "core-osv",
  "document_id": 286042,
  "published_at": "2026-10-11T13:47:03+00:00"
}