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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2020-26287 Detail

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.


Severity

 


CVSS 3.x Severity and Metrics:

NIST CVSS score matches with CNA score
CNA:  GitHub, Inc.
Base Score:  8.7 HIGH
Vector:  CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N


NVD Analysts use publicly available information to associate vector strings and CVSS scores. We also display any CVSS information provided within the CVE List from the CNA.

Note: The NVD and the CNA have provided the same score. When this occurs only the CNA information is displayed, but the Acceptance Level icon for the CNA is given a checkmark to signify NVD concurrence.

References to Advisories, Solutions, and Tools

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Hyperlink Resource
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 
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 

Weakness Enumeration

CWE-ID CWE Name Source
CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') cwe source acceptance level NIST   Provider acceptance level GitHub, Inc.  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2020-26287
NVD Published Date:
12/28/2020
NVD Last Modified:
12/30/2020
Source:
GitHub, Inc.