CVE-2018-1000813 : Security Advisory and Response

This CVE involves a Cross Site Scripting (XSS) vulnerability in versions 1.11.0 and earlier of Backdrop CMS, allowing the execution of JavaScript code from an unexpected source.

Understanding CVE-2018-1000813

This vulnerability was assigned on November 27, 2018, and has been resolved in version 1.11.1 and subsequent releases.

What is CVE-2018-1000813?

The XSS vulnerability in Backdrop CMS versions 1.11.0 and earlier arises from inadequate sanitization of custom class names used on blocks and layouts. It enables the execution of JavaScript code from an unanticipated source, requiring a user to be intentionally directed to a specific page while logged in.

The Impact of CVE-2018-1000813

The vulnerability allows malicious actors to execute JavaScript code on affected pages, potentially leading to unauthorized actions or data theft.

Technical Details of CVE-2018-1000813

This section provides more in-depth technical insights into the vulnerability.

Vulnerability Description

The XSS flaw in Backdrop CMS versions 1.11.0 and earlier stems from improper sanitization of custom class names on blocks and layouts, enabling the execution of JavaScript from unexpected sources.

Affected Systems and Versions

Backdrop CMS versions 1.11.0 and earlier are vulnerable to this XSS issue.

Exploitation Mechanism

To exploit this vulnerability, a user must be intentionally directed to a specific page while logged in, allowing the execution of malicious JavaScript code.

Mitigation and Prevention

Protecting systems from CVE-2018-1000813 requires immediate actions and long-term security practices.

Immediate Steps to Take

Update Backdrop CMS to version 1.11.1 or later to mitigate the vulnerability.
Educate users to avoid clicking on suspicious links or visiting untrusted websites.

Long-Term Security Practices

Implement strict input validation and output encoding to prevent XSS attacks.
Regularly monitor and audit web applications for security vulnerabilities.

Patching and Updates

Regularly apply security patches and updates provided by Backdrop CMS to address known vulnerabilities.