mal-2026-17595
Vulnerability from ossf_malicious_packages
Published
2026-10-05 07:10
Modified
2026-10-11 14:20
Summary
Malicious code in crypto-mnemonic-tools (RubyGems)
Details

RubyGems runs this gem's native extension script ext/req_throttle_mini/extconf.rb during gem install. The script exits without action on CI runners and sandboxes, based on CI environment variables, the hostname, the username and the working directory. It continues if the system uptime is over 30 minutes and the home directory holds .ssh, .gitconfig, .npmrc, .gem/credentials or .bundle. It then decodes a Base64 Ruby payload, forks twice into a detached process, waits 20 to 40 minutes and opens a reverse shell that connects /bin/sh to 45.138.12.177 on TCP port 8090. The shell reconnects every 30 seconds. The Ruby code in lib/ is a decoy. The RubyGems account reqthrottle_3474 published this gem and 41 others with the same loader on 2026-10-05.


-= Per source details. Do not edit below this line.=-

Source: amazon-inspector (44e296902c4b40fc0d6e6c2e431aa5e2a6e60002ddb1c6cb7619d3c4da5854f3)

The gem advertises itself as a BIP-39 mnemonic helper but ships an ext/req_throttle_mini/extconf.rb native-extension script with no C sources alongside it. On gem install, the extconf.rb decodes a base64 Ruby payload and evals it inside a detached, double-forked daemon that opens a TCPSocket to 45.138.12.177:8090 and bridges it to /bin/sh via IO.popen(['/bin/sh'], 'r+') and an IO.copy_stream loop, giving a remote operator interactive shell on the installer's host. Process.setsid, double fork, Process.detach, and reopening std streams to /dev/null background the shell so the install completes normally. Execution is gated by anti-analysis checks that skip CI environments (CI, GITHUB_ACTIONS, TRAVIS, JENKINS_URL, GITLAB_CI, CODESPACES), ephemeral/sandbox hostnames (uvm, firecracker, sandbox, vagrant), generated/analyst usernames, analysis working directories (/opt/rubygems, /tmp, /var/tmp, /workspace), and hosts with uptime under 1800 seconds, and additionally requires developer artifacts (~/.ssh, ~/.gitconfig, ~/.npmrc, ~/.gem/credentials, ~/.bundle) to be present before firing. The script then sleeps 1200+rand(1200) seconds before connecting to delay the egress past install-time monitoring. The extconf.rb calls create_makefile('crypto_mnemonic_tools_native') as a stub with no accompanying native source, so the extension exists solely as an install-time execution vector. The lure name targets developers handling crypto wallet mnemonics, whose workstations are the gated-for target.

Source: ossf-package-analysis (bb822e92dde37e6e686752599f3fe9e8b7006769c01fb2693c5c2303112709a4)

The OpenSSF Package Analysis project identified 'crypto-mnemonic-tools' @ 1.0.0 (rubygems) as malicious.

It is considered malicious because:

  • The package executes one or more commands associated with malicious behavior.
CWE
  • CWE-506 - The product contains code that appears to be malicious in nature.
  • CWE-506 - The product contains code that appears to be malicious in nature.
  • CWE-506 - The product contains code that appears to be malicious in nature.

{
  "affected": [
    {
      "database_specific": {
        "cwes": [
          {
            "cweId": "CWE-506",
            "description": "The product contains code that appears to be malicious in nature.",
            "name": "Embedded Malicious Code"
          },
          {
            "cweId": "CWE-506",
            "description": "The product contains code that appears to be malicious in nature.",
            "name": "Embedded Malicious Code"
          },
          {
            "cweId": "CWE-506",
            "description": "The product contains code that appears to be malicious in nature.",
            "name": "Embedded Malicious Code"
          }
        ],
        "indicators": {
          "evidence_files": [
            {
              "path": "ext/req_throttle_mini/extconf.rb",
              "sha256": "207d37e45638330df97d82727fee2942056606051db821c879aebc1306b93e48",
              "tlsh": "2e517856cf8359e91ae1c0c0457d9012f6a3ab0a50646875f3ee0868ff59b76c1f12fe"
            },
            {
              "path": "metadata.yaml",
              "sha256": "6e38978c019db3496c5439129fb0f1d9dca08652393379a5eb30eb6ec79e7201",
              "tlsh": "7121e181fadbf83af581d6d148b07613e3b3d90c7d562f018ba791c413ce069670b261"
            }
          ]
        }
      },
      "package": {
        "ecosystem": "RubyGems",
        "name": "crypto-mnemonic-tools"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "1.0.0",
        "1.0.3"
      ]
    }
  ],
  "credits": [
    {
      "contact": [
        "inspector-research@amazon.com"
      ],
      "name": "Amazon Inspector",
      "type": "FINDER"
    },
    {
      "contact": [
        "https://github.com/ossf/package-analysis",
        "https://openssf.slack.com/channels/package_analysis"
      ],
      "name": "OpenSSF: Package Analysis",
      "type": "FINDER"
    },
    {
      "contact": [
        "https://safedep.io"
      ],
      "name": "SafeDep",
      "type": "FINDER"
    }
  ],
  "database_specific": {
    "iocs": {
      "files": [
        {
          "digests": {
            "sha256": "207d37e45638330df97d82727fee2942056606051db821c879aebc1306b93e48"
          },
          "note": "Native extension script that RubyGems runs at install time. It gates on the environment and starts the payload.",
          "paths": [
            "ext/req_throttle_mini/extconf.rb"
          ],
          "source": "PACKAGE_ARCHIVE"
        }
      ],
      "ips": [
        "45.138.12.177"
      ]
    },
    "malicious-packages-origins": [
      {
        "id": "IN-MAL-2026-021037",
        "import_time": "2026-10-05T16:22:53.924298304Z",
        "modified_time": "2026-10-05T15:54:59Z",
        "sha256": "20550e421f034d2bf7c4ca653a79a2558f3d84a49a54566e874d92cc80557469",
        "source": "amazon-inspector",
        "versions": [
          "1.0.0"
        ]
      },
      {
        "import_time": "2026-10-06T00:50:51.033876381Z",
        "modified_time": "2026-10-05T07:10:39Z",
        "sha256": "bb822e92dde37e6e686752599f3fe9e8b7006769c01fb2693c5c2303112709a4",
        "source": "ossf-package-analysis",
        "versions": [
          "1.0.0"
        ]
      },
      {
        "id": "IN-MAL-2026-021374",
        "import_time": "2026-10-11T14:18:00.33032129Z",
        "modified_time": "2026-10-11T13:49:39Z",
        "sha256": "44e296902c4b40fc0d6e6c2e431aa5e2a6e60002ddb1c6cb7619d3c4da5854f3",
        "source": "amazon-inspector",
        "versions": [
          "1.0.3"
        ]
      }
    ]
  },
  "details": "RubyGems runs this gem\u0027s native extension script `ext/req_throttle_mini/extconf.rb` during `gem install`. The script exits without action on CI runners and sandboxes, based on CI environment variables, the hostname, the username and the working directory. It continues if the system uptime is over 30 minutes and the home directory holds `.ssh`, `.gitconfig`, `.npmrc`, `.gem/credentials` or `.bundle`. It then decodes a Base64 Ruby payload, forks twice into a detached process, waits 20 to 40 minutes and opens a reverse shell that connects `/bin/sh` to 45.138.12.177 on TCP port 8090. The shell reconnects every 30 seconds. The Ruby code in `lib/` is a decoy. The RubyGems account `reqthrottle_3474` published this gem and 41 others with the same loader on 2026-10-05.\n\n---\n_-= Per source details. Do not edit below this line.=-_\n\n## Source: amazon-inspector (44e296902c4b40fc0d6e6c2e431aa5e2a6e60002ddb1c6cb7619d3c4da5854f3)\nThe gem advertises itself as a BIP-39 mnemonic helper but ships an `ext/req_throttle_mini/extconf.rb` native-extension script with no C sources alongside it. On `gem install`, the extconf.rb decodes a base64 Ruby payload and `eval`s it inside a detached, double-forked daemon that opens a TCPSocket to 45.138.12.177:8090 and bridges it to `/bin/sh` via `IO.popen([\u0027/bin/sh\u0027], \u0027r+\u0027)` and an `IO.copy_stream` loop, giving a remote operator interactive shell on the installer\u0027s host. Process.setsid, double fork, Process.detach, and reopening std streams to /dev/null background the shell so the install completes normally. Execution is gated by anti-analysis checks that skip CI environments (CI, GITHUB_ACTIONS, TRAVIS, JENKINS_URL, GITLAB_CI, CODESPACES), ephemeral/sandbox hostnames (uvm, firecracker, sandbox, vagrant), generated/analyst usernames, analysis working directories (/opt/rubygems, /tmp, /var/tmp, /workspace), and hosts with uptime under 1800 seconds, and additionally requires developer artifacts (~/.ssh, ~/.gitconfig, ~/.npmrc, ~/.gem/credentials, ~/.bundle) to be present before firing. The script then sleeps 1200+rand(1200) seconds before connecting to delay the egress past install-time monitoring. The extconf.rb calls `create_makefile(\u0027crypto_mnemonic_tools_native\u0027)` as a stub with no accompanying native source, so the extension exists solely as an install-time execution vector. The lure name targets developers handling crypto wallet mnemonics, whose workstations are the gated-for target.\n\n## Source: ossf-package-analysis (bb822e92dde37e6e686752599f3fe9e8b7006769c01fb2693c5c2303112709a4)\nThe OpenSSF Package Analysis project identified \u0027crypto-mnemonic-tools\u0027 @ 1.0.0 (rubygems) as malicious.\n\nIt is considered malicious because:\n\n- The package executes one or more commands associated with malicious behavior.\n",
  "id": "MAL-2026-17595",
  "modified": "2026-10-11T14:20:02.617428423Z",
  "published": "2026-10-05T07:10:39Z",
  "references": [
    {
      "type": "PACKAGE",
      "url": "https://rubygems.org/gems/crypto-mnemonic-tools/versions/1.0.0"
    },
    {
      "type": "REPORT",
      "url": "https://safedep.io/rubygems-crypto-gems-install-time-reverse-shell/"
    },
    {
      "type": "PACKAGE",
      "url": "https://rubygems.org/gems/crypto-mnemonic-tools/versions/1.0.3"
    }
  ],
  "schema_version": "1.7.4",
  "summary": "Malicious code in crypto-mnemonic-tools (RubyGems)"
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Loading…

Loading…

Loading…

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.


Loading…