{
  "GSD": {
    "alias": "CVE-2021-43809",
    "description": "`Bundler` is a package for managing application dependencies in Ruby. In `bundler` versions before 2.2.33, when working with untrusted and apparently harmless `Gemfile`\u0027s, it is not expected that they lead to execution of external code, unless that\u0027s explicit in the ruby code inside the `Gemfile` itself. However, if the `Gemfile` includes `gem` entries that use the `git` option with invalid, but seemingly harmless, values with a leading dash, this can be false. To handle dependencies that come from a Git repository instead of a registry, Bundler uses various commands, such as `git clone`. These commands are being constructed using user input (e.g. the repository URL). When building the commands, Bundler versions before 2.2.33 correctly avoid Command Injection vulnerabilities by passing an array of arguments instead of a command string. However, there is the possibility that a user input starts with a dash (`-`) and is therefore treated as an optional argument instead of a positional one. This can lead to Code Execution because some of the commands have options that can be leveraged to run arbitrary executables. Since this value comes from the `Gemfile` file, it can contain any character, including a leading dash. To exploit this vulnerability, an attacker has to craft a directory containing a `Gemfile` file that declares a dependency that is located in a Git repository. This dependency has to have a Git URL in the form of `-u./payload`. This URL will be used to construct a Git clone command but will be interpreted as the upload-pack argument. Then this directory needs to be shared with the victim, who then needs to run a command that evaluates the Gemfile, such as `bundle lock`, inside. This vulnerability can lead to Arbitrary Code Execution, which could potentially lead to the takeover of the system. However, the exploitability is very low, because it requires a lot of user interaction. Bundler 2.2.33 has patched this problem by inserting `--` as an argument before any positional arguments to those Git commands that were affected by this issue. Regardless of whether users can upgrade or not, they should review any untrustred `Gemfile`\u0027s before running any `bundler` commands that may read them, since they can contain arbitrary ruby code.",
    "id": "GSD-2021-43809",
    "references": [
      "https://www.suse.com/security/cve/CVE-2021-43809.html",
      "https://security.archlinux.org/CVE-2021-43809",
      "https://advisories.mageia.org/CVE-2021-43809.html"
    ]
  },
  "gsd": {
    "metadata": {
      "exploitCode": "unknown",
      "remediation": "unknown",
      "reportConfidence": "confirmed",
      "type": "vulnerability"
    },
    "osvSchema": {
      "affected": [
        {
          "package": {
            "ecosystem": "RubyGems",
            "name": "bundler",
            "purl": "pkg:gem/bundler"
          }
        }
      ],
      "aliases": [
        "CVE-2021-43809",
        "GHSA-fj7f-vq84-fh43"
      ],
      "details": "In `bundler` versions before 2.2.33, when working with untrusted and apparently harmless\n`Gemfile`\u0027s, it is not expected that they lead to execution of external code, unless\nthat\u0027s explicit in the ruby code inside the `Gemfile` itself. However, if the `Gemfile`\nincludes `gem` entries that use the `git` option with invalid, but seemingly harmless,\nvalues with a leading dash, this can be false.\n\nTo handle dependencies that come from a Git repository instead of a registry, Bundler\nuses various commands, such as `git clone`. These commands are being constructed using\nuser input (e.g. the repository URL). When building the commands, Bundler versions\nbefore 2.2.33 correctly avoid Command Injection vulnerabilities by passing an array of\narguments instead of a command string. However, there is the possibility that a user\ninput starts with a dash (`-`) and is therefore treated as an optional argument instead\nof a positional one. This can lead to Code Execution because some of the commands have\noptions that can be leveraged to run arbitrary executables.\n\nSince this value comes from the `Gemfile` file, it can contain any character, including\na leading dash.\n\n### Exploitation\n\nTo exploit this vulnerability, an attacker has to craft a directory containing a\n`Gemfile` file that declares a dependency that is located in a Git repository. This\ndependency has to have a Git URL in the form of `-u./payload`. This URL will be used to\nconstruct a Git clone command but will be interpreted as the\n[upload-pack](https://git-scm.com/docs/git-clone#Documentation/git-clone.txt--ultupload-packgt)\nargument. Then this directory needs to be shared with the victim, who then needs to run\na command that evaluates the Gemfile, such as `bundle lock`, inside.\n\n### Impact\n\nThis vulnerability can lead to Arbitrary Code Execution, which could potentially lead\nto the takeover of the system. However, as explained above, the exploitability is very\nlow, because it requires a lot of user interaction. It still could put developers at\nrisk when dealing with untrusted files in a way they think is safe, because the exploit\nstill works when the victim tries to make sure nothing can happen, e.g. by manually\nreviewing the `Gemfile` (although they would need the weird URL with a leading dash to\nnot raise any flags).\n\nThis kind of attack vector\n[has been used in the past](https://www.cnbc.com/2021/01/26/north-korean-hackers-targeting-security-researchers-on-twitter.html)\nto target security researchers by sending them projects to collaborate on.\n\n### Patches\n\nBundler 2.2.33 has patched this problem by inserting `--` as an argument before any\npositional arguments to those Git commands that were affected by this issue.\n\n### Workarounds\n\nRegardless of whether users can upgrade or not, they should review any untrusted\n`Gemfile`\u0027s before running any `bundler` commands that may read them, since they\ncan contain arbitrary ruby code.",
      "id": "GSD-2021-43809",
      "modified": "2021-12-08T00:00:00.000Z",
      "published": "2021-12-08T00:00:00.000Z",
      "references": [
        {
          "type": "WEB",
          "url": "https://github.com/rubygems/rubygems/security/advisories/GHSA-fj7f-vq84-fh43"
        },
        {
          "type": "WEB",
          "url": "https://github.com/rubygems/rubygems/pull/5142"
        },
        {
          "type": "WEB",
          "url": "https://github.com/rubygems/rubygems/commit/0fad1ccfe9dd7a3c5b82c1496df3c2b4842870d3"
        },
        {
          "type": "WEB",
          "url": "https://github.com/rubygems/rubygems/commit/a4f2f8ac17e6ce81c689527a8b6f14381060d95f"
        },
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          "type": "WEB",
          "url": "https://cwe.mitre.org/data/definitions/88.html"
        }
      ],
      "schema_version": "1.4.0",
      "severity": [
        {
          "score": 6.7,
          "type": "CVSS_V3"
        }
      ],
      "summary": "Local Code Execution through Argument Injection via dash leading git url parameter in Gemfile"
    }
  },
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            "value": "`Bundler` is a package for managing application dependencies in Ruby. In `bundler` versions before 2.2.33, when working with untrusted and apparently harmless `Gemfile`\u0027s, it is not expected that they lead to execution of external code, unless that\u0027s explicit in the ruby code inside the `Gemfile` itself. However, if the `Gemfile` includes `gem` entries that use the `git` option with invalid, but seemingly harmless, values with a leading dash, this can be false. To handle dependencies that come from a Git repository instead of a registry, Bundler uses various commands, such as `git clone`. These commands are being constructed using user input (e.g. the repository URL). When building the commands, Bundler versions before 2.2.33 correctly avoid Command Injection vulnerabilities by passing an array of arguments instead of a command string. However, there is the possibility that a user input starts with a dash (`-`) and is therefore treated as an optional argument instead of a positional one. This can lead to Code Execution because some of the commands have options that can be leveraged to run arbitrary executables. Since this value comes from the `Gemfile` file, it can contain any character, including a leading dash.\n\nTo exploit this vulnerability, an attacker has to craft a directory containing a `Gemfile` file that declares a dependency that is located in a Git repository. This dependency has to have a Git URL in the form of `-u./payload`. This URL will be used to construct a Git clone command but will be interpreted as the upload-pack argument. Then this directory needs to be shared with the victim, who then needs to run a command that evaluates the Gemfile, such as `bundle lock`, inside.\n\nThis vulnerability can lead to Arbitrary Code Execution, which could potentially lead to the takeover of the system. However, the exploitability is very low, because it requires a lot of user interaction. Bundler 2.2.33 has patched this problem by inserting `--` as an argument before any positional arguments to those Git commands that were affected by this issue. Regardless of whether users can upgrade or not, they should review any untrustred `Gemfile`\u0027s before running any `bundler` commands that may read them, since they can contain arbitrary ruby code."
          }
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      "impact": {
        "cvss": [
          {
            "attackComplexity": "HIGH",
            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 6.7,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
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                "cweId": "CWE-88",
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                "value": "CWE-88: Improper Neutralization of Argument Delimiters in a Command (\u0027Argument Injection\u0027)"
              }
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            "name": "https://github.com/rubygems/rubygems/security/advisories/GHSA-fj7f-vq84-fh43",
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            "url": "https://github.com/rubygems/rubygems/security/advisories/GHSA-fj7f-vq84-fh43"
          },
          {
            "name": "https://github.com/rubygems/rubygems/pull/5142",
            "refsource": "MISC",
            "url": "https://github.com/rubygems/rubygems/pull/5142"
          },
          {
            "name": "https://github.com/rubygems/rubygems/commit/0fad1ccfe9dd7a3c5b82c1496df3c2b4842870d3",
            "refsource": "MISC",
            "url": "https://github.com/rubygems/rubygems/commit/0fad1ccfe9dd7a3c5b82c1496df3c2b4842870d3"
          },
          {
            "name": "https://github.com/rubygems/rubygems/commit/a4f2f8ac17e6ce81c689527a8b6f14381060d95f",
            "refsource": "MISC",
            "url": "https://github.com/rubygems/rubygems/commit/a4f2f8ac17e6ce81c689527a8b6f14381060d95f"
          },
          {
            "name": "https://www.sonarsource.com/blog/securing-developer-tools-package-managers/",
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            "url": "https://www.sonarsource.com/blog/securing-developer-tools-package-managers/"
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      "source": {
        "advisory": "GHSA-fj7f-vq84-fh43",
        "discovery": "UNKNOWN"
      }
    },
    "github.com/rubysec/ruby-advisory-db": {
      "cve": "2021-43809",
      "cvss_v3": 6.7,
      "date": "2021-12-08",
      "description": "In `bundler` versions before 2.2.33, when working with untrusted and apparently harmless\n`Gemfile`\u0027s, it is not expected that they lead to execution of external code, unless\nthat\u0027s explicit in the ruby code inside the `Gemfile` itself. However, if the `Gemfile`\nincludes `gem` entries that use the `git` option with invalid, but seemingly harmless,\nvalues with a leading dash, this can be false.\n\nTo handle dependencies that come from a Git repository instead of a registry, Bundler\nuses various commands, such as `git clone`. These commands are being constructed using\nuser input (e.g. the repository URL). When building the commands, Bundler versions\nbefore 2.2.33 correctly avoid Command Injection vulnerabilities by passing an array of\narguments instead of a command string. However, there is the possibility that a user\ninput starts with a dash (`-`) and is therefore treated as an optional argument instead\nof a positional one. This can lead to Code Execution because some of the commands have\noptions that can be leveraged to run arbitrary executables.\n\nSince this value comes from the `Gemfile` file, it can contain any character, including\na leading dash.\n\n### Exploitation\n\nTo exploit this vulnerability, an attacker has to craft a directory containing a\n`Gemfile` file that declares a dependency that is located in a Git repository. This\ndependency has to have a Git URL in the form of `-u./payload`. This URL will be used to\nconstruct a Git clone command but will be interpreted as the\n[upload-pack](https://git-scm.com/docs/git-clone#Documentation/git-clone.txt--ultupload-packgt)\nargument. Then this directory needs to be shared with the victim, who then needs to run\na command that evaluates the Gemfile, such as `bundle lock`, inside.\n\n### Impact\n\nThis vulnerability can lead to Arbitrary Code Execution, which could potentially lead\nto the takeover of the system. However, as explained above, the exploitability is very\nlow, because it requires a lot of user interaction. It still could put developers at\nrisk when dealing with untrusted files in a way they think is safe, because the exploit\nstill works when the victim tries to make sure nothing can happen, e.g. by manually\nreviewing the `Gemfile` (although they would need the weird URL with a leading dash to\nnot raise any flags).\n\nThis kind of attack vector\n[has been used in the past](https://www.cnbc.com/2021/01/26/north-korean-hackers-targeting-security-researchers-on-twitter.html)\nto target security researchers by sending them projects to collaborate on.\n\n### Patches\n\nBundler 2.2.33 has patched this problem by inserting `--` as an argument before any\npositional arguments to those Git commands that were affected by this issue.\n\n### Workarounds\n\nRegardless of whether users can upgrade or not, they should review any untrusted\n`Gemfile`\u0027s before running any `bundler` commands that may read them, since they\ncan contain arbitrary ruby code.",
      "gem": "bundler",
      "ghsa": "fj7f-vq84-fh43",
      "patched_versions": [
        "\u003e= 2.2.33"
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      "related": {
        "url": [
          "https://github.com/rubygems/rubygems/pull/5142",
          "https://github.com/rubygems/rubygems/commit/0fad1ccfe9dd7a3c5b82c1496df3c2b4842870d3",
          "https://github.com/rubygems/rubygems/commit/a4f2f8ac17e6ce81c689527a8b6f14381060d95f",
          "https://cwe.mitre.org/data/definitions/88.html"
        ]
      },
      "title": "Local Code Execution through Argument Injection via dash leading git url parameter in Gemfile",
      "url": "https://github.com/rubygems/rubygems/security/advisories/GHSA-fj7f-vq84-fh43"
    },
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          "affected_range": "\u003c2.2.33",
          "affected_versions": "All versions before 2.2.33",
          "cvss_v2": "AV:N/AC:M/Au:N/C:C/I:C/A:C",
          "cvss_v3": "CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H",
          "cwe_ids": [
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            "CWE-88",
            "CWE-937"
          ],
          "date": "2021-12-13",
          "description": "`Bundler` is a package for managing application dependencies in Ruby. In `bundler` when working with untrusted and apparently harmless `Gemfile`\u0027s, it is not expected that they lead to execution of external code, unless that\u0027s explicit in the ruby code inside the `Gemfile` itself. However, if the `Gemfile` includes `gem` entries that use the `git` option with invalid, but seemingly harmless, values with a leading dash, this can be false. To handle dependencies that come from a Git repository instead of a registry, Bundler uses various commands, such as `git clone`. These commands are being constructed using user input (e.g. the repository URL). When building the commands, Bundler versions before 2.2.33 correctly avoid Command Injection vulnerabilities by passing an array of arguments instead of a command string. However, there is the possibility that a user input starts with a dash (`-`) and is therefore treated as an optional argument instead of a positional one. This can lead to Code Execution because some of the commands have options that can be leveraged to run arbitrary executables. Since this value comes from the `Gemfile` file, it can contain any character, including a leading dash. To exploit this vulnerability, an attacker has to craft a directory containing a `Gemfile` file that declares a dependency that is located in a Git repository. This dependency has to have a Git URL in the form of `-u./payload`. This URL will be used to construct a Git clone command but will be interpreted as the upload-pack argument. Then this directory needs to be shared with the victim, who then needs to run a command that evaluates the Gemfile, such as `bundle lock`, inside. This vulnerability can lead to Arbitrary Code Execution, which could potentially lead to the takeover of the system. However, the exploitability is very low, because it requires a lot of user interaction. Bundler 2.2.33 has patched this problem by inserting `--` as an argument before any positional arguments to those Git commands that were affected by this issue. Regardless of whether users can upgrade or not, they should review any untrusted `Gemfile`\u0027s before running any `bundler` commands that may read them, since they can contain arbitrary ruby code.",
          "fixed_versions": [
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          "not_impacted": "All versions starting from 2.2.33",
          "package_slug": "gem/bundler",
          "pubdate": "2021-12-08",
          "solution": "Upgrade to version 2.2.33 or above.",
          "title": "Improper Neutralization of Argument Delimiters in a Command (\u0027Argument Injection\u0027)",
          "urls": [
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            "authentication": "NONE",
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            "baseScore": 9.3,
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            "vectorString": "AV:N/AC:M/Au:N/C:C/I:C/A:C",
            "version": "2.0"
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          "exploitabilityScore": 8.6,
          "impactScore": 10.0,
          "obtainAllPrivilege": false,
          "obtainOtherPrivilege": false,
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            "baseScore": 7.3,
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      },
      "lastModifiedDate": "2023-11-16T03:04Z",
      "publishedDate": "2021-12-08T19:15Z"
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}

{
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      "ranges": [
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            },
            {
              "fixed": "2.2.33"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2021-43809"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-88"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2021-12-08T19:33:42Z",
    "nvd_published_at": "2021-12-08T19:15:00Z",
    "severity": "MODERATE"
  },
  "details": "In `bundler` versions before 2.2.33, when working with untrusted and apparently harmless `Gemfile`\u0027s, it is not expected that they lead to execution of external code, unless that\u0027s explicit in the ruby code inside the `Gemfile` itself. However, if the `Gemfile` includes `gem` entries that use the `git` option with invalid, but seemingly harmless, values with a leading dash, this can be false.\n\nTo handle dependencies that come from a Git repository instead of a registry, Bundler uses various commands, such as `git clone`. These commands are being constructed using user input (e.g. the repository URL). When building the\ncommands, Bundler versions before 2.2.33 correctly avoid Command Injection vulnerabilities by passing an array of arguments instead of a command string. However, there is the possibility that a user input starts with a dash (`-`) and is therefore treated as an optional argument instead of a positional one. This can lead to Code Execution because some of the commands have options that can be leveraged to run arbitrary executables.\n\nSince this value comes from the `Gemfile` file, it can contain any character, including a leading dash.\n\n### Exploitation\n\nTo exploit this vulnerability, an attacker has to craft a directory containing a `Gemfile` file that declares a dependency that is located in a Git repository. This dependency has to have a Git URL in the form of `-u./payload`. This URL\nwill be used to construct a Git clone command but will be interpreted as the [upload-pack](https://git-scm.com/docs/git-clone#Documentation/git-clone.txt--ultupload-packgt) argument. Then this directory needs to be shared with the victim, who then needs to run a command that evaluates the Gemfile, such as `bundle lock`, inside.\n\n### Impact\n\nThis vulnerability can lead to Arbitrary Code Execution, which could potentially lead to the takeover of the system. However, as explained above, the exploitability is very low, because it requires a lot of user interaction. It still could put developers at risk when dealing with untrusted files in a way they think is safe, because the exploit still works when the victim tries to make sure nothing can happen, e.g. by manually reviewing the `Gemfile` (although they would need the weird URL with a leading dash to not raise any flags).\n\nThis kind of attack vector [has been used in the past](https://www.cnbc.com/2021/01/26/north-korean-hackers-targeting-security-researchers-on-twitter.html) to target security researchers by sending them projects to collaborate on.\n\n### Patches\n\nBundler 2.2.33 has patched this problem by inserting `--` as an argument before any positional arguments to those Git commands that were affected by this issue.\n\n### Workarounds\n\nRegardless of whether users can upgrade or not, they should review any untrustred `Gemfile`\u0027s before running any `bundler` commands that may read them, since they can contain arbitrary ruby code.\n\n### References\n\nhttps://cwe.mitre.org/data/definitions/88.html",
  "id": "GHSA-fj7f-vq84-fh43",
  "modified": "2021-12-14T15:31:09Z",
  "published": "2021-12-08T19:51:36Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/rubygems/rubygems/security/advisories/GHSA-fj7f-vq84-fh43"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-43809"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rubygems/rubygems/pull/5142"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rubygems/rubygems/commit/0fad1ccfe9dd7a3c5b82c1496df3c2b4842870d3"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rubygems/rubygems/commit/a4f2f8ac17e6ce81c689527a8b6f14381060d95f"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/rubygems/rubygems"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/bundler/CVE-2021-43809.yml"
    },
    {
      "type": "WEB",
      "url": "https://www.sonarsource.com/blog/securing-developer-tools-package-managers"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "Local Code Execution through Argument Injection via dash leading git url parameter in Gemfile."
}