CVE-2021-20185 : What You Need to Know
Discover the impact of CVE-2021-20185 on Moodle versions before 3.10.1, 3.9.4, 3.8.7, and 3.5.16. Learn about the denial of service risk and mitigation steps to secure your Moodle platform.
A vulnerability was discovered in Moodle versions before 3.10.1, 3.9.4, 3.8.7, and 3.5.16 that could lead to a denial of service due to unrestricted character limits in messaging.
Understanding CVE-2021-20185
This CVE highlights a security issue in Moodle versions prior to 3.10.1, 3.9.4, 3.8.7, and 3.5.16 related to messaging functionalities.
What is CVE-2021-20185?
The vulnerability in Moodle allowed unlimited characters in messages, potentially causing denial of service on the client-side, specifically browser-based, for users receiving excessively large messages.
The Impact of CVE-2021-20185
Exploitation of this vulnerability could result in a denial of service (DoS) for users who receive abnormally large messages, impacting the accessibility and usability of the Moodle platform.
Technical Details of CVE-2021-20185
This section provides specific technical details related to the CVE.
Vulnerability Description
The issue arises from a lack of character limits in messaging within Moodle versions before 3.10.1, 3.9.4, 3.8.7, and 3.5.16, enabling the potential for DoS attacks.
Affected Systems and Versions
Moodle versions 3.10.1, 3.9.4, 3.8.7, and 3.5.16 are confirmed to be impacted by this vulnerability due to the lack of character limitations in messaging.
Exploitation Mechanism
Attackers could exploit this vulnerability by sending disproportionately large messages, overwhelming the recipient's browser and causing a denial of service.
Mitigation and Prevention
To address CVE-2021-20185, immediate actions and long-term security measures are recommended.
Immediate Steps to Take
Users are advised to update their Moodle instances to versions 3.10.1, 3.9.4, 3.8.7, or 3.5.16 to mitigate the risk of DoS due to unlimited character messaging.
Long-Term Security Practices
Implementing regular security patches, monitoring message content, and educating users on safe messaging practices can enhance the overall security posture of Moodle installations.
Patching and Updates
Regularly check and apply software updates and patches released by Moodle to ensure that your system remains secure from known vulnerabilities.