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GHSA-3M6G-2423-7CP3

Vulnerability from github – Published: 2026-03-19 12:45 – Updated: 2026-03-25 18:24
VLAI
Summary
Ruby JSON has a format string injection vulnerability
Details

Impact

A format string injection vulnerability than that lead to denial of service attacks or information disclosure, when the allow_duplicate_key: false parsing option is used to parse user supplied documents.

This option isn't the default, if you didn't opt-in to use it, you are not impacted.

Patches

Patched in 2.19.2.

Workarounds

The issue can be avoided by not using the allow_duplicate_key: false parsing option.

Severity
8.3 (High)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N
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{
  "affected": [
    {
      "package": {
        "ecosystem": "RubyGems",
        "name": "json"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.18.0"
            },
            {
              "fixed": "2.19.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "RubyGems",
        "name": "json"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.16.0"
            },
            {
              "fixed": "2.17.1.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "RubyGems",
        "name": "json"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "2.14.0"
            },
            {
              "fixed": "2.15.2.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-33210"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-134"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-03-19T12:45:53Z",
    "nvd_published_at": "2026-03-20T23:16:46Z",
    "severity": "HIGH"
  },
  "details": "### Impact\n\nA format string injection vulnerability than that lead to denial of service attacks or information disclosure, when the `allow_duplicate_key: false` parsing option is used to parse user supplied documents. \n\nThis option isn\u0027t the default, if you didn\u0027t opt-in to use it, you are not impacted.\n\n### Patches\n\nPatched in `2.19.2`.\n\n### Workarounds\n\nThe issue can be avoided by not using the `allow_duplicate_key: false` parsing option.",
  "id": "GHSA-3m6g-2423-7cp3",
  "modified": "2026-03-25T18:24:34Z",
  "published": "2026-03-19T12:45:53Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/ruby/json/security/advisories/GHSA-3m6g-2423-7cp3"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-33210"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/ruby/json"
    },
    {
      "type": "WEB",
      "url": "https://github.com/rubysec/ruby-advisory-db/blob/master/gems/json/CVE-2026-33210.yml"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Ruby JSON has a format string injection vulnerability"
}



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