SB2021010407 - Multiple vulnerabilities in Umbraco CMS



SB2021010407 - Multiple vulnerabilities in Umbraco CMS

Published: January 4, 2021

Security Bulletin ID SB2021010407
Severity
Medium
Patch available
YES
Number of vulnerabilities 3
Exploitation vector Remote access
Highest impact Data manipulation

Breakdown by Severity

Medium 33% Low 67%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 3 secuirty vulnerabilities.


1) Stored cross-site scripting (CVE-ID: CVE-2020-5809)

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 iframes in rich-text content editor. A remote authenticated attacker can permanently 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.


2) Stored cross-site scripting (CVE-ID: CVE-2020-5810)

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 uploaded .svg files in media. A remote authenticated attacker can permanently 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.


3) Path traversal (CVE-ID: CVE-2020-5811)

The vulnerability allows a remote attacker to perform directory traversal attacks.

The vulnerability exists due to input validation error during package installation. A remote authenticated attacker can send a specially crafted HTTP request and write arbitrary files on the system.


Remediation

Install update from vendor's website.