CVE-2021-23002 is a medium severity vulnerability affecting F5's BIG-IP Access Policy Manager (APM). Specifically, it allows the session ID to be visible in the arguments of the f5vpn.exe command when launching a VPN from a browser on a Windows system. This exposure could lead to unauthorized access if an attacker can intercept this information. The CVSS score for this vulnerability is 4.5, indicating a moderate level of risk. Organizations must address it promptly to prevent potential exploitation.
The vulnerability affects several versions of BIG-IP APM, including 16.0.x before 16.0.1.1, 15.1.x before 15.1.2.1, 14.1.x before 14.1.4, 13.1.x before 13.1.3.6, and all 12.1.x and 11.6.x versions. Additionally, Edge Client versions 7.2.1.x before 7.2.1.1, 7.1.9.x before 7.1.9.8, and 7.1.8.x before 7.1.8.5 are affected. Given the widespread use of these versions, it's crucial for organizations to prioritize remediation efforts.
The urgency for organizations is underscored by the fact that addressing this issue requires both client and server fixes. Therefore, it is essential to ensure that all components are updated to secure versions. If not patched, organizations risk exposing sensitive session information, which could be leveraged by attackers.
Organizations should be aware that software versions that have reached End of Software Development (EoSD) are not evaluated for this vulnerability. Thus, it is advised to upgrade to supported versions to maintain security posture and compliance.
In light of these factors, organizations need to prioritize patching immediately to mitigate the risks associated with this vulnerability.
Vulnerability Details
The official description of CVE-2021-23002 states: 'When using BIG-IP APM 16.0.x before 16.0.1.1, 15.1.x before 15.1.2.1, 14.1.x before 14.1.4, 13.1.x before 13.1.3.6, or all 12.1.x and 11.6.x versions or Edge Client versions 7.2.1.x before 7.2.1.1, 7.1.9.x before 7.1.9.8, or 7.1.8.x before 7.1.8.5, the session ID is visible in the arguments of the f5vpn.exe command when VPN is launched from the browser on a Windows system. Addressing this issue requires both the client and server fixes.'
This vulnerability falls under the category of information disclosure, with a CVSS score of 4.5 categorized as medium severity. The affected products include 'access_policy_manager_clients' and 'big-ip_access_policy_manager'. The vulnerability was published on March 31, 2021, and is classified under CVSS version 3.1.
Technical Analysis
The root cause of CVE-2021-23002 lies in the improper handling of sensitive session identifiers, which are exposed during the VPN connection process. The attack vector is classified as 'Adjacent Network', meaning that an attacker must be on the same local network to exploit this vulnerability.
The attack complexity is low, as there are no special conditions required for exploitation. A high privilege level is required to initiate the f5vpn.exe command, but no user interaction is necessary to reveal the session ID, making it easier for an attacker to leverage this vulnerability effectively.
In terms of impact, the confidentiality of session IDs is classified as high, as unauthorized access to these identifiers could lead to further compromise of the network. However, there is no impact on integrity or availability, as the vulnerability does not affect the core functionality of the applications involved.
Risk & Impact Analysis
The real-world deployment risk associated with CVE-2021-23002 is significant, particularly for organizations relying on F5's BIG-IP APM for secure remote access. The exposure of session IDs could allow attackers to hijack user sessions, leading to unauthorized access to sensitive information or systems.
This vulnerability matters to organizations because of the potential for data breaches and the subsequent legal and reputational consequences. The blast radius is considerable due to the widespread use of affected versions in enterprise environments. Organizations should assess the likelihood of exploitation based on their specific network architecture and threat landscape.
Given the CVSS score of 4.5 and the absence of any known exploits, organizations should still treat this vulnerability with urgency. As remote work continues to be prevalent, organizations must maintain a proactive security posture to safeguard against risks posed by unpatched vulnerabilities.
Signal | Status |
|---|---|
Known Exploit | No |
Public PoC | No |
Actively Exploited | No |
Ransomware Use | No |
Affected Versions
CVE-2021-23002 affects multiple versions of F5 BIG-IP APM, specifically versions 16.0.x before 16.0.1.1, 15.1.x before 15.1.2.1, 14.1.x before 14.1.4, 13.1.x before 13.1.3.6, and all versions of 12.1.x and 11.6.x. Additionally, Edge Client versions 7.2.1.x before 7.2.1.1, 7.1.9.x before 7.1.9.8, and 7.1.8.x before 7.1.8.5 are also impacted. Organizations should verify their systems and update any affected components.
Mitigation & Remediation
To mitigate the risks associated with CVE-2021-23002, organizations must apply patches and updates provided by F5. It is essential to upgrade to the latest versions of BIG-IP APM and Edge Client to ensure vulnerabilities are addressed. If immediate patching is not possible, organizations should implement configuration hardening and restrict access to the VPN to minimize exposure.
Organizations should also consider conducting regular security assessments, including penetration testing to identify potential weaknesses in their systems.
Monitoring network traffic for any abnormal behavior, conducting regular audits, and maintaining incident response plans are also critical measures to enhance security.
Detection Guidance
Organizations should implement logging mechanisms that capture commands executed within the VPN context. Monitoring for unusual access patterns or repeated attempts to access the VPN can help detect potential exploitation. Additionally, behavioral anomalies related to user sessions should be investigated to ensure session integrity.
Network signatures that can identify unauthorized access attempts should be established, and system changes must be closely monitored to detect any unauthorized modifications.
AppSecure Threat Intelligence Insight
The long-term significance of CVE-2021-23002 lies in its illustration of how sensitive information can be improperly handled within widely used software. This vulnerability serves as a reminder to organizations of the importance of secure coding practices and thorough testing before software deployment.
The trend this vulnerability represents highlights the need for enhanced security measures in remote access solutions, particularly as the shift towards remote work increases. Security teams must be vigilant and proactive in addressing vulnerabilities to protect against potential breaches.
Organizations can benefit from adopting a comprehensive security strategy, including regular updates, security assessments, and adherence to best practices in application security. For more insights on improving security posture, organizations can explore topics such as vulnerability management programs and penetration testing methodologies to strengthen their defenses.
Finally, organizations should remain informed about the evolving threat landscape and ensure that their security measures adapt accordingly.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
.webp)