CVE-2020-28907 in Fusion
Summary
by MITRE • 05/24/2021
Incorrect SSL certificate validation in Nagios Fusion 4.1.8 and earlier allows for Escalation of Privileges or Code Execution as root via vectors related to download of an untrusted update package in upgrade_to_latest.sh.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 05/27/2021
The vulnerability identified as CVE-2020-28907 represents a critical security flaw in Nagios Fusion versions 4.1.8 and earlier, specifically targeting the software's SSL certificate validation mechanisms. This weakness enables attackers to bypass essential security controls during the update process, creating a pathway for privilege escalation and potential code execution with root-level privileges. The vulnerability manifests within the upgrade_to_latest.sh script which handles the download and installation of update packages, making it a critical component in the attack chain.
The technical root cause of this vulnerability stems from improper SSL certificate validation during the download of untrusted update packages. When Nagios Fusion attempts to download updates, the system fails to properly verify the authenticity and integrity of the SSL certificates presented by the remote servers. This validation failure creates an opportunity for man-in-the-middle attacks where attackers can intercept and modify update packages without detection. The flaw aligns with CWE-295, which specifically addresses improper certificate validation, and represents a classic example of how weak cryptographic validation can compromise entire software ecosystems. The vulnerability operates through the ATT&CK framework's T1059.007 technique for command and script injection, as the compromised update package can execute arbitrary code with elevated privileges.
The operational impact of CVE-2020-28907 is severe and far-reaching, as it allows attackers to gain root-level access to systems running vulnerable Nagios Fusion versions. This privilege escalation capability means that an attacker who successfully exploits this vulnerability can completely compromise the monitoring infrastructure, potentially gaining access to sensitive network data, system configurations, and other critical assets. The implications extend beyond simple code execution, as the attacker can manipulate the monitoring system to hide malicious activities, alter security alerts, or establish persistent backdoors within the network infrastructure. Organizations relying on Nagios Fusion for critical system monitoring face significant risk of undetected compromise, as the vulnerability can remain hidden while the attacker maintains elevated privileges.
Mitigation strategies for CVE-2020-28907 should prioritize immediate patching of affected Nagios Fusion installations to version 4.1.9 or later, where the SSL validation issues have been addressed. Organizations should implement additional network-level controls such as certificate pinning for update servers, network segmentation to isolate monitoring systems, and enhanced monitoring of update processes to detect anomalous behavior. The implementation of proper certificate validation procedures and regular security audits of update mechanisms should be enforced across all monitoring infrastructure. Security teams should also consider deploying intrusion detection systems specifically configured to monitor for suspicious update activities and establish strict policies for verifying update package integrity before installation. This vulnerability underscores the critical importance of maintaining up-to-date security controls and proper cryptographic validation in enterprise monitoring systems, as highlighted by the NIST Cybersecurity Framework's emphasis on continuous monitoring and vulnerability management.