{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "cpe": "cpe:2.3:a:nodeca:js-yaml:*:*:*:*:*:node.js:*:*",
            "extracted_events": [
              {
                "introduced": "3.0.0"
              },
              {
                "fixed": "3.15.0"
              },
              {
                "introduced": "4.0.0"
              },
              {
                "fixed": "4.3.0"
              }
            ],
            "source": [
              "CPE_RANGE",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "b58544b370043e30fe976aad6d62bb133325750e"
            },
            {
              "fixed": "c34b6c40027a769eb0d67958ae615268a1d55f54"
            },
            {
              "introduced": "ee74ce4b4800282b2f23b776be7dc95dfe34db1c"
            },
            {
              "fixed": "33d05b5d29a8c21360f620f7e1c1706e24522eda"
            },
            {
              "fixed": "24f13e79ee1343a7e30bd6f6c9d9cdbf0ac9b2b7"
            },
            {
              "fixed": "59423c6f8cdc78742ac00e25a4dd39ef16b702e4"
            }
          ],
          "repo": "https://github.com/nodeca/js-yaml",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-52cp-r559-cp3m"
  ],
  "database_specific": {
    "cna_assigner": "GitHub_M",
    "cwe_ids": [
      "CWE-407"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59869.json"
  },
  "details": "js-yaml is a JavaScript YAML parser and dumper. From 3.0.0 before 3.15.0 and from 4.0.0 before 4.3.0, js-yaml can spend quadratic CPU time parsing a document whose size grows only linearly when a chain of mappings uses merge keys where each mapping merges the previous one. This issue is fixed in versions 3.15.0 and 4.3.0.",
  "id": "CVE-2026-59869",
  "modified": "2026-07-16T03:30:49.953431535Z",
  "published": "2026-07-08T15:15:54.675Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/nodeca/js-yaml/releases/tag/3.15.0"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nodeca/js-yaml/releases/tag/4.3.0"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/59xxx/CVE-2026-59869.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/nodeca/js-yaml/security/advisories/GHSA-52cp-r559-cp3m"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-59869"
    },
    {
      "type": "FIX",
      "url": "https://github.com/nodeca/js-yaml/commit/24f13e79ee1343a7e30bd6f6c9d9cdbf0ac9b2b7"
    },
    {
      "type": "FIX",
      "url": "https://github.com/nodeca/js-yaml/commit/59423c6f8cdc78742ac00e25a4dd39ef16b702e4"
    }
  ],
  "schema_version": "1.8.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "js-yaml: YAML merge-key chains can force quadratic CPU consumption"
}