CVE-2020-26287

Published Dec 29, 2020

Last updated 4 years ago

Overview

Description
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.
Source
security-advisories@github.com
NVD status
Analyzed

Risk scores

CVSS 3.1

Type
Primary
Base score
8.7
Impact score
5.8
Exploitability score
2.3
Vector string
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N
Severity
HIGH

CVSS 2.0

Type
Primary
Base score
4.3
Impact score
2.9
Exploitability score
8.6
Vector string
AV:N/AC:M/Au:N/C:N/I:P/A:N

Weaknesses

nvd@nist.gov
CWE-79
security-advisories@github.com
CWE-79

Social media

Hype score
Not currently trending

Configurations