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.
References
Link | Resource |
---|---|
https://github.com/hedgedoc/hedgedoc/releases/tag/1.7.1 | Third Party Advisory |
https://github.com/hedgedoc/hedgedoc/security/advisories/GHSA-g6w6-7xf9-m95p | Third Party Advisory |
https://github.com/Alemmi/ctf-writeups/blob/main/hxpctf-2020/hackme/solution.md | Exploit Third Party Advisory |
https://github.com/hackmdio/codimd/issues/1630 | Third Party Advisory |
https://github.com/hedgedoc/hedgedoc/commit/58276ebbf4504a682454a3686dcaff88bc1069d4 | Patch Third Party Advisory |
Configurations
Information
Published : 2020-12-28 16:15
Updated : 2020-12-30 08:50
NVD link : CVE-2020-26287
Mitre link : CVE-2020-26287
JSON object : View
CWE
CWE-79
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Products Affected
hedgedoc
- hedgedoc