MAL-2026-17582

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Import Source
https://github.com/ossf/malicious-packages/blob/main/osv/malicious/rubygems/bitciin/MAL-2026-17582.json
JSON Data
https://api.osv.dev/v1/vulns/MAL-2026-17582
Published
2026-10-05T08:00:31Z
Modified
2026-10-06T01:00:16Z
Summary
Malicious code in bitciin (RubyGems)
Details

RubyGems runs this gem's native extension script ext/bitciin/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 and forks twice into a detached process. After 20 to 40 minutes the payload downloads http://45.138.12.177:8092/wgkit.tar.gz to /tmp/.w1.tgz with curl, extracts it to /tmp/.w1/, runs wg_install.sh with bash and deletes both. The payload stores the URL XOR-encoded with the key usv\x9a. 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 (73144cb471499af4467e7c8c2a6da34013285179444e101290faa7ec9fda0a19)

The gem declares a native extension (ext/bitciin/extconf.rb) that runs during gem install. The shipped C source (ext/bitciin/bitciin.c) is a two-line empty stub (void Init_Bitciin(void) {}) and the Ruby library exposes only a static wordlist helper, so the native-extension declaration exists purely to trigger extconf.rb. extconf.rb applies a sandbox-evasion gate (checks for CI environment variables, hostname/username/cwd regexes, uptime > 1800s, and presence of ~/.ssh, ~/.gitconfig, ~/.gem/credentials, ~/.bundle, and /.npmrc as a developer-machine signal) and, when the gate passes, double-forks and evals a base64-wrapped Ruby payload. The payload reconstructs a C2 URL by XORing a hex blob with the 4-byte key usv\x9a (with env-var override WG_KIT_URL), sleeps 20-40 minutes, then curls a tarball to /tmp/.w1.tgz and executes bash /tmp/.w1/wg_install.sh. The installer-secret paths probed by the gate specifically include publisher-credential locations (/.gem/credentials, ~/.npmrc), consistent with a credential-targeted stage-2.

Source: ossf-package-analysis (63fda57a3acbe357c8cc9b7bc0a2f619fac4928bab9a794fb5960d0ee0e6d54b)

The OpenSSF Package Analysis project identified 'bitciin' @ 1.0.0 (rubygems) as malicious.

It is considered malicious because:

  • The package executes one or more commands associated with malicious behavior.
Database specific 
{
    "iocs":  {
        "files":  [
            {
                "digests":  {
                    "sha256":  "977d0764ae375bd6a338c2dd9a3e55ea732a20b19fb9b0ec035171bb8f39f68e"
                },
                "note":  "Native extension script that RubyGems runs at install time. It gates on the environment and starts the payload.",
                "paths":  [
                    "ext/bitciin/extconf.rb"
                ],
                "source":  "PACKAGE_ARCHIVE"
            },
            {
                "note":  "Second-stage archive and install script downloaded and run by the payload.",
                "paths":  [
                    "/tmp/.w1.tgz",
                    "/tmp/.w1/wg_install.sh"
                ],
                "source":  "DROPPED"
            }
        ],
        "ips":  [
            "45.138.12.177"
        ],
        "urls":  [
            "http://45.138.12.177:8092/wgkit.tar.gz"
        ]
    },
    "malicious-packages-origins":  [
        {
            "id":  "IN-MAL-2026-021058",
            "import_time":  "2026-10-05T16:22:55.428472327Z",
            "modified_time":  "2026-10-05T15:58:03Z",
            "sha256":  "73144cb471499af4467e7c8c2a6da34013285179444e101290faa7ec9fda0a19",
            "source":  "amazon-inspector",
            "versions":  [
                "1.0.0"
            ]
        },
        {
            "import_time":  "2026-10-06T00:50:49.425267233Z",
            "modified_time":  "2026-10-05T08:00:31Z",
            "sha256":  "63fda57a3acbe357c8cc9b7bc0a2f619fac4928bab9a794fb5960d0ee0e6d54b",
            "source":  "ossf-package-analysis",
            "versions":  [
                "1.0.0"
            ]
        }
    ]
}
References
Credits

Affected packages

RubyGems / bitciin

Package

Name
bitciin
Purl
pkg:gem/bitciin

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0 Unknown introduced version / All previous versions are affected

Affected versions

1.*
1.0.0

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"
    }
]
indicators 
{
    "evidence_files":  [
        {
            "path":  "ext/bitciin/extconf.rb",
            "sha256":  "977d0764ae375bd6a338c2dd9a3e55ea732a20b19fb9b0ec035171bb8f39f68e",
            "tlsh":  "6851db568b8395f54db1d0d044355412fb667b0d6068ac64f3de086cbb5af2ac4f02fd"
        },
        {
            "path":  "ext/bitciin/bitciin.c",
            "sha256":  "3ea6f0ef00d7fe7e8436de537736458949461e26f1cc4904956a49d523a9351a"
        }
    ]
}
source 
"https://github.com/ossf/malicious-packages/blob/main/osv/malicious/rubygems/bitciin/MAL-2026-17582.json"