CVE-2023-49792 : Vulnerability Insights and Analysis
Learn about CVE-2023-49792 impacting Nextcloud Server versions, allowing brute-force protection bypass due to misconfigured reverse proxy. Find mitigation steps here.
This CVE-2023-49792 involves Nextcloud Server and Nextcloud Enterprise Server versions prior to 26.0.9 and 27.1.4, and 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, and 27.1.4 respectively. It allows bypassing of brute-force protection due to misconfigured proxy settings.
Understanding CVE-2023-49792
Nextcloud Server is a data storage solution for the Nextcloud cloud platform. Vulnerabilities in versions mentioned above can be exploited by attackers to execute more authentication attempts than intended.
What is CVE-2023-49792?
The CVE-2023-49792 vulnerability in Nextcloud Server arises when a trusted reverse proxy is misconfigured, leading to the server misinterpreting the remote address of the attacker. This allows attackers to bypass authentication protections.
The Impact of CVE-2023-49792
An attacker exploiting CVE-2023-49792 can launch excessive authentication attempts, potentially gaining unauthorized access to sensitive data stored on the affected Nextcloud Server versions.
Technical Details of CVE-2023-49792
Vulnerability Description
Nextcloud Server versions prior to 26.0.9 and 27.1.4, and Nextcloud Enterprise Server versions prior to 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, and 27.1.4 are affected. The issue stems from misconfigured trusted proxies.
Affected Systems and Versions
- Vendor: nextcloud
- Product: security-advisories
- Versions: >= 23.0.0, < 23.0.12.13; >= 24.0.0, < 24.0.12.9; >= 25.0.0, < 25.0.13.4; >= 26.0.0, < 26.0.9; >= 27.0.0, < 27.1.4
Exploitation Mechanism
Attackers can manipulate the proxy configuration to mislead the server into reading an incorrect remote address, enabling them to perform unauthorized authentication attempts.
Mitigation and Prevention
Immediate Steps to Take
Users of affected Nextcloud Server versions should update to the patched versions, namely 26.0.9 and 27.1.4, or Nextcloud Enterprise Server versions 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, and 27.1.4. It is crucial to reconfigure proxy settings securely.
Long-Term Security Practices
Regularly review and update proxy configurations, follow security advisories from Nextcloud, and implement strong authentication mechanisms to prevent unauthorized access to servers.
Patching and Updates
Apply patches provided by Nextcloud promptly to address CVE-2023-49792 and other security vulnerabilities. Stay informed about security best practices to enhance the overall security posture of your Nextcloud environment.