CVE-2021-26829 : Exploit Details and Defense Strategies

OpenPLC ScadaBR through 0.9.1 on Linux and through 1.12.4 on Windows is affected by a stored XSS vulnerability via system_settings.shtm.

Understanding CVE-2021-26829

This CVE highlights the security issue in OpenPLC ScadaBR that allows malicious actors to execute stored XSS attacks.

What is CVE-2021-26829?

CVE-2021-26829 pertains to the ability of an attacker to execute stored cross-site scripting (XSS) attacks in OpenPLC ScadaBR through specific system settings pages.

The Impact of CVE-2021-26829

This vulnerability could be exploited by attackers to inject malicious scripts into the system, potentially leading to unauthorized access, data theft, or further compromise of the affected systems.

Technical Details of CVE-2021-26829

The technical details of this vulnerability include:

Vulnerability Description

The vulnerability in OpenPLC ScadaBR allows for the storage of malicious scripts through system_settings.shtm, opening the door for XSS attacks.

Affected Systems and Versions

OpenPLC ScadaBR versions up to 0.9.1 on Linux and up to 1.12.4 on Windows are affected by this vulnerability.

Exploitation Mechanism

Attackers can exploit this vulnerability by injecting malicious scripts into the system settings pages, which can be triggered when unsuspecting users interact with the affected pages.

Mitigation and Prevention

To safeguard systems from CVE-2021-26829, the following measures are recommended:

Immediate Steps to Take

Update OpenPLC ScadaBR to the latest version that includes a patch for this XSS vulnerability.
Avoid interacting with suspicious or untrusted links that can potentially execute scripts on the system.

Long-Term Security Practices

Regularly monitor security advisories and updates from OpenPLC to stay informed about potential vulnerabilities.
Implement strong input validation mechanisms to prevent the execution of malicious scripts.

Patching and Updates

It is crucial to apply patches and updates provided by OpenPLC ScadaBR promptly to mitigate the risk of XSS attacks.