CVE-2020-26287

Summary

HedgeDoc is a collaborative platform for writing and sharing markdown. In HedgeDoc before version 1.7.1 an attacker can inject arbitrary script tags in HedgeDoc notes using mermaid diagrams. Our content security policy prevents loading scripts from most locations, but www.google-analytics.com is allowed. Using Google Tag Manger it is possible to inject arbitrary JavaScript and execute it on page load. Depending on the configuration of the instance, the attacker may not need authentication to create or edit notes. The problem is patched in HedgeDoc 1.7.1. As a workaround one can disallow www.google-analytics.com in the Content-Security-Policy header. Note that other ways to leverage the script tag injection might exist.

Affected Software

VendorProductVersion RangeStatus
hedgedochedgedoc< 1.7.1affected

Weaknesses

  • CWE-79: CWE-79 Cross-site Scripting (XSS)

ADP Enrichment

CVE Program Container

Additional References

References