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CVE-2021-29503

Published: 2021-05-19T20:15Z
Last Modified: 2024-11-21T06:01Z
Source: MITRE CVE List
License: MITRE-CVE-TOS
HedgeDoc is a platform to write and share markdown. HedgeDoc before version 1.8.2 is vulnerable to a cross-site scripting attack using the YAML-metadata of a note. An attacker with write access to a note can embed HTML tags in the Open Graph metadata section of the note, resulting in the frontend rendering the script tag as part of the `<head>` section. Unless your instance prevents guests from editing notes, this vulnerability allows unauthenticated attackers to inject JavaScript into notes that allow guest edits. If your instance prevents guests from editing notes, this vulnerability allows authenticated attackers to inject JavaScript into any note pages they have write-access to. This vulnerability is patched in version 1.8.2. As a workaround, one can disable guest edits until the next update. > MITRE Terms of Use apply – see LICENSE‑MITRE.txt