CVE-2024-33509 in FortiWeb
Summary
by MITRE • 07/09/2024
An improper certificate validation vulnerability [CWE-295] in FortiWeb 7.2.0 through 7.2.1, 7.0 all versions, 6.4 all versions and 6.3 all versions may allow a remote and unauthenticated attacker in a Man-in-the-Middle position to decipher and/or tamper with the communication channel between the device and different endpoints used to fetch data for Web Application Firewall (WAF).
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Analysis
by VulDB Data Team • 09/09/2024
The vulnerability identified as CVE-2024-33509 represents a critical improper certificate validation flaw classified under CWE-295 within FortiWeb web application firewall products. This security weakness affects multiple versions including 7.2.0 through 7.2.1, all versions of 7.0, 6.4, and 6.3 series, creating a widespread impact across Fortinet's FortiWeb product line. The flaw specifically targets the certificate validation mechanisms that are fundamental to establishing secure communication channels between the FortiWeb appliance and various backend endpoints responsible for fetching data for WAF operations.
The technical implementation of this vulnerability allows a remote and unauthenticated attacker who has positioned themselves in a man-in-the-middle attack scenario to exploit the weak certificate validation processes. When the FortiWeb device attempts to establish secure connections with backend services, the improper validation allows malicious actors to intercept, decipher, and tamper with the communication channel without requiring authentication credentials or physical access to the network infrastructure. This weakness directly undermines the core security principle of certificate-based authentication that is essential for protecting data integrity and confidentiality in web application security systems.
The operational impact of this vulnerability extends beyond simple data interception, as it enables attackers to manipulate the communication between the FortiWeb appliance and its data sources. This compromise can lead to unauthorized access to sensitive backend information, potential data exfiltration, and the ability to inject malicious content into the web application firewall's operational processes. The vulnerability affects the fundamental trust model that FortiWeb relies upon for secure WAF operations, potentially allowing attackers to bypass security controls and gain unauthorized access to web applications protected by the compromised appliance.
Organizations utilizing affected FortiWeb versions face significant risk exposure as this vulnerability can be exploited remotely without any authentication requirements. The man-in-the-middle positioning requirement means that attackers do not need to be directly connected to the network but can leverage existing network vulnerabilities or compromised network paths to position themselves effectively. This makes the attack surface particularly broad as attackers can exploit the vulnerability from various network positions, including public internet access points or through compromised internal network segments. The vulnerability's presence in multiple version lines indicates a fundamental flaw in the certificate validation implementation that requires immediate attention across affected deployments.
Mitigation strategies should prioritize immediate patching of affected FortiWeb versions to address the certificate validation implementation. Organizations should implement network segmentation and monitoring to detect potential man-in-the-middle attacks targeting the FortiWeb appliances. Additional defensive measures include implementing enhanced network monitoring for unusual communication patterns between FortiWeb and backend services, deploying intrusion detection systems that can identify certificate validation anomalies, and conducting thorough network assessments to identify potential attack vectors. The vulnerability aligns with ATT&CK techniques related to credential access and defense evasion, particularly targeting the T1566.001 technique for credential harvesting through man-in-the-middle attacks. Organizations should also consider implementing certificate pinning mechanisms and enhanced logging of certificate validation events to detect potential exploitation attempts.