{"api_version":"1","generated_at":"2026-07-08T18:28:11+00:00","cve":"CVE-2026-59869","urls":{"html":"https://cve.report/CVE-2026-59869","api":"https://cve.report/api/cve/CVE-2026-59869.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-59869","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-59869"},"summary":{"title":"js-yaml: YAML merge-key chains can force quadratic CPU consumption","description":"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.","state":"PUBLISHED","assigner":"GitHub_M","published_at":"2026-07-08 16:16:33","updated_at":"2026-07-08 16:16:33"},"problem_types":["CWE-407","CWE-407 CWE-407: Inefficient Algorithmic Complexity"],"metrics":[{"version":"3.1","source":"security-advisories@github.com","type":"Secondary","score":"7.5","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"7.5","severity":"HIGH","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","data":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"references":[{"url":"https://github.com/nodeca/js-yaml/security/advisories/GHSA-52cp-r559-cp3m","name":"https://github.com/nodeca/js-yaml/security/advisories/GHSA-52cp-r559-cp3m","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/nodeca/js-yaml/commit/59423c6f8cdc78742ac00e25a4dd39ef16b702e4","name":"https://github.com/nodeca/js-yaml/commit/59423c6f8cdc78742ac00e25a4dd39ef16b702e4","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/nodeca/js-yaml/releases/tag/4.3.0","name":"https://github.com/nodeca/js-yaml/releases/tag/4.3.0","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/nodeca/js-yaml/releases/tag/3.15.0","name":"https://github.com/nodeca/js-yaml/releases/tag/3.15.0","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://github.com/nodeca/js-yaml/commit/24f13e79ee1343a7e30bd6f6c9d9cdbf0ac9b2b7","name":"https://github.com/nodeca/js-yaml/commit/24f13e79ee1343a7e30bd6f6c9d9cdbf0ac9b2b7","refsource":"security-advisories@github.com","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-59869","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-59869","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"nodeca","product":"js-yaml","version":"affected >= 3.0.0, < 3.15.0","platforms":[]},{"source":"CNA","vendor":"nodeca","product":"js-yaml","version":"affected >= 4.0.0, < 4.3.0","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"product":"js-yaml","vendor":"nodeca","versions":[{"status":"affected","version":">= 3.0.0, < 3.15.0"},{"status":"affected","version":">= 4.0.0, < 4.3.0"}]}],"descriptions":[{"lang":"en","value":"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."}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":7.5,"baseSeverity":"HIGH","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-407","description":"CWE-407: Inefficient Algorithmic Complexity","lang":"en","type":"CWE"}]}],"providerMetadata":{"dateUpdated":"2026-07-08T15:15:54.675Z","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M"},"references":[{"name":"https://github.com/nodeca/js-yaml/security/advisories/GHSA-52cp-r559-cp3m","tags":["x_refsource_CONFIRM"],"url":"https://github.com/nodeca/js-yaml/security/advisories/GHSA-52cp-r559-cp3m"},{"name":"https://github.com/nodeca/js-yaml/commit/24f13e79ee1343a7e30bd6f6c9d9cdbf0ac9b2b7","tags":["x_refsource_MISC"],"url":"https://github.com/nodeca/js-yaml/commit/24f13e79ee1343a7e30bd6f6c9d9cdbf0ac9b2b7"},{"name":"https://github.com/nodeca/js-yaml/commit/59423c6f8cdc78742ac00e25a4dd39ef16b702e4","tags":["x_refsource_MISC"],"url":"https://github.com/nodeca/js-yaml/commit/59423c6f8cdc78742ac00e25a4dd39ef16b702e4"},{"name":"https://github.com/nodeca/js-yaml/releases/tag/3.15.0","tags":["x_refsource_MISC"],"url":"https://github.com/nodeca/js-yaml/releases/tag/3.15.0"},{"name":"https://github.com/nodeca/js-yaml/releases/tag/4.3.0","tags":["x_refsource_MISC"],"url":"https://github.com/nodeca/js-yaml/releases/tag/4.3.0"}],"source":{"advisory":"GHSA-52cp-r559-cp3m","discovery":"UNKNOWN"},"title":"js-yaml: YAML merge-key chains can force quadratic CPU consumption"}},"cveMetadata":{"assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","assignerShortName":"GitHub_M","cveId":"CVE-2026-59869","datePublished":"2026-07-08T15:15:54.675Z","dateReserved":"2026-07-07T15:41:53.607Z","dateUpdated":"2026-07-08T15:15:54.675Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-07-08 16:16:33","lastModifiedDate":"2026-07-08 16:16:33","problem_types":["CWE-407","CWE-407 CWE-407: Inefficient Algorithmic Complexity"],"metrics":{"cvssMetricV31":[{"source":"security-advisories@github.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"HIGH"},"exploitabilityScore":3.9,"impactScore":3.6}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"59869","Ordinal":"1","Title":"js-yaml: YAML merge-key chains can force quadratic CPU consumpti","CVE":"CVE-2026-59869","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"59869","Ordinal":"1","NoteData":"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.","Type":"Description","Title":"js-yaml: YAML merge-key chains can force quadratic CPU consumpti"}]}}}