Legora before 2026-08-14 contains a cross-site scripting vulnerability that allows attackers to achieve arbitrary JavaScript execution in a victim's browser by embedding a Mermaid block prefixed with a gray-matter JavaScript front-matter directive, causing the front-matter parser to invoke eval() before any SVG sanitization occurs. Attackers can exploit this flaw through influenced Mermaid diagram content to execute arbitrary JavaScript in the user's browser context, with elevated impact on Word and Outlook add-in surfaces where bearer session tokens are persisted in localStorage.
Metrics
Affected Vendors & Products
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History
Fri, 21 Aug 2026 13:00:00 +0000
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Legora
Legora legora |
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Legora
Legora legora |
Mon, 17 Aug 2026 20:30:00 +0000
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ssvc
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Mon, 17 Aug 2026 20:00:00 +0000
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| Description | Legora before 2026-08-14 contains a cross-site scripting vulnerability that allows attackers to achieve arbitrary JavaScript execution in a victim's browser by embedding a Mermaid block prefixed with a gray-matter JavaScript front-matter directive, causing the front-matter parser to invoke eval() before any SVG sanitization occurs. Attackers can exploit this flaw through influenced Mermaid diagram content to execute arbitrary JavaScript in the user's browser context, with elevated impact on Word and Outlook add-in surfaces where bearer session tokens are persisted in localStorage. | |
| Title | Legora < 2026-08-14 XSS via Mermaid gray-matter JavaScript Engine | |
| Weaknesses | CWE-95 | |
| References |
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| Metrics |
cvssV3_1
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Status: PUBLISHED
Assigner: VulnCheck
Published: 2026-08-17T19:38:05.767Z
Updated: 2026-08-21T19:56:53.812Z
Reserved: 2026-08-14T18:01:19.917Z
Link: CVE-2026-74234
Updated: 2026-08-17T19:55:31.824Z
Status : Received
Published: 2026-08-17T20:16:46.813
Modified: 2026-08-21T20:16:40.867
Link: CVE-2026-74234
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