markdown-it is a Markdown parser. From versions 14.1.0 to before 14.3.3, and 15.0.0 to before 15.0.3, a link reference definition whose label or title is never closed is O(n²) with default options. Continuation lines are pulled lazily with str += lineContent in src/rules_block/reference.ts, and the subsequent charCodeAt and slice calls flatten the V8 cons-string, copying everything collected so far; this runs before the rule decides the definition is invalid. No options are required to trigger it. This issue has been patched in versions 14.3.3 and 15.0.3.
{
"cna_assigner": "GitHub_M",
"cwe_ids": [
"CWE-400",
"CWE-407"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/111xxx/CVE-2026-111758.json",
"unresolved_ranges": [
{
"extracted_events": [
{
"range": [
{
"introduced": "14.1.0"
},
{
"fixed": "14.3.3"
},
{
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},
{
"fixed": "15.0.3"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StringRangeExpression"
}
]
},
{
"extracted_events": [
{
"range": [
{
"fixed": "14.3.3"
},
{
"fixed": "15.0.3"
},
{
"fixed": "14.3.3"
}
],
"source": "DESCRIPTION"
}
]
}
]
}{
"extracted_events": [
{
"range": [
{
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}
],
"source": "REFERENCES_COMMIT"
},
{
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],
"source": "REFERENCES_COMMIT"
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{
"original_tag": "14.3.3",
"range": [
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"source": "REFERENCES_TAG"
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}
],
"source": "REFERENCES_TAG"
}
]
}