CVE-2021-32741 Explained : Impact and Mitigation
Discover the impact of CVE-2021-32741, a vulnerability in Nextcloud Server versions, enabling attackers to enumerate potentially valid share tokens. Learn how to mitigate and prevent exploitation.
Nextcloud Server versions prior to 19.0.13, 20.0.11, and 21.0.3 are affected by a vulnerability due to a lack of ratelimiting on the public share link mount endpoint. An attacker could potentially enumerate valid share tokens.
Understanding CVE-2021-32741
This CVE identifies the lack of ratelimiting vulnerability on the public share link mount endpoint in Nextcloud Server versions.
What is CVE-2021-32741?
In Nextcloud Server versions below 19.0.13, 20.0.11, and 21.0.3, the absence of ratelimiting on the public share link mount endpoint allowed attackers to potentially discover valid share tokens.
The Impact of CVE-2021-32741
The exploitation of this vulnerability could lead to unauthorized access to sensitive data and compromise the integrity of the affected systems.
Technical Details of CVE-2021-32741
This section delves into the specific technical aspects of the vulnerability.
Vulnerability Description
The vulnerability stems from the lack of ratelimiting on the public share link mount endpoint, enabling attackers to enumerate potentially valid share tokens.
Affected Systems and Versions
Nextcloud Server versions prior to 19.0.13, 20.0.11, and 21.0.3 are impacted by this vulnerability.
Exploitation Mechanism
Attackers could exploit this vulnerability by utilizing the lack of ratelimiting on the public share link mount endpoint to enumerate valid share tokens.
Mitigation and Prevention
To address CVE-2021-32741, immediate actions and long-term security practices are recommended.
Immediate Steps to Take
Upgrade Nextcloud Server to the fixed versions 19.0.13, 20.0.11, or 21.0.3 to mitigate the vulnerability. Regularly monitor for security advisories and apply patches promptly.
Long-Term Security Practices
Implement proper access controls, regularly audit configurations, and conduct security training to enhance overall cybersecurity posture.
Patching and Updates
Stay informed about security updates from Nextcloud and apply patches as soon as they are released to safeguard your systems.