CVE-2021-21259 HIGH

CVE-2021-21259: Stored XSS in slide mode

Vendor Hedgedoc
Product hedgedoc
Weakness CWE-79 · XSS
Published January 22, 2021
Last update August 3, 2024

CVSS base score

7.4/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction Required
Confidentiality None
Integrity High

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N

What the vulnerability does

01Description

HedgeDoc is open source software which lets you create real-time collaborative markdown notes. In HedgeDoc before version 1.7.2, an attacker can inject arbitrary JavaScript into a HedgeDoc note, which is executed when the note is viewed in slide mode. Depending on the configuration of the instance, the attacker may not need authentication to create or edit notes. The problem is patched in HedgeDoc 1.7.2. As a workaround, disallow loading JavaScript from 3rd party sites using the `Content-Security-Policy` header. Note that this will break some embedded content.

Key dates

02Disclosure timeline

January 22, 2021 CVE published
August 3, 2024 Record updated