Stored cross-site scripting in HedgeDoc - CVE-2020-26287
Published: December 29, 2020 / Updated: January 4, 2021
Vulnerability identifier: #VU49233
CSH Severity: Low
CVSSv4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N/E:U/U:Clear
CVE-ID: CVE-2020-26287
CWE-ID: CWE-79
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerable software:
HedgeDoc
HedgeDoc
Software vendor:
HedgeDoc
HedgeDoc
Description
The disclosed vulnerability allows a remote attacker to perform cross-site scripting (XSS) attacks.
The vulnerability exists due to insufficient sanitization of user-supplied data within mermaid diagrams. A remote attacker can inject and execute arbitrary HTML and script code in user's browser in context of vulnerable website.
Successful exploitation of this vulnerability may allow a remote attacker to steal potentially sensitive information, change appearance of the web page, perform phishing and drive-by-download attacks.
Remediation
Install updates from vendor's website.
External links
- https://github.com/Alemmi/ctf-writeups/blob/main/hxpctf-2020/hackme/solution.md
- https://github.com/hackmdio/codimd/issues/1630
- https://github.com/hedgedoc/hedgedoc/commit/58276ebbf4504a682454a3686dcaff88bc1069d4
- https://github.com/hedgedoc/hedgedoc/releases/tag/1.7.1
- https://github.com/hedgedoc/hedgedoc/security/advisories/GHSA-g6w6-7xf9-m95p