CVE-2016-5022 in BIG-IP
Summary
by MITRE
F5 BIG-IP LTM, Analytics, APM, ASM, and Link Controller 11.2.x before 11.2.1 HF16, 11.3.x, 11.4.x, 11.5.x before 11.5.4 HF2, 11.6.x before 11.6.1 HF1, and 12.x before 12.0.0 HF3; BIG-IP AAM, AFM, and PEM 11.4.x, 11.5.x before 11.5.4 HF2, 11.6.x before 11.6.1 HF1, and 12.x before 12.0.0 HF3; BIG-IP DNS 12.x before 12.0.0 HF3; BIG-IP Edge Gateway, WebAccelerator, and WOM 11.2.x before 11.2.1 HF16 and 11.3.0; BIG-IP GTM 11.2.x before 11.2.1 HF16, 11.3.x, 11.4.x, 11.5.x before 11.5.4 HF2, and 11.6.x before 11.6.1 HF1; BIG-IP PSM 11.2.x before 11.2.1 HF16, 11.3.x, and 11.4.0 through 11.4.1; Enterprise Manager 3.1.1; BIG-IQ Cloud and Security 4.0.0 through 4.5.0; BIG-IQ Device 4.2.0 through 4.5.0; BIG-IQ ADC 4.5.0; BIG-IQ Centralized Management 5.0.0; BIG-IQ Cloud and Orchestration 1.0.0; and iWorkflow 2.0.0, when Packet Filtering is enabled on virtual servers and possibly self IP addresses, allow remote attackers to cause a denial of service (Traffic Management Microkernel restart) and possibly have unspecified other impact via crafted network traffic.
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Analysis
by VulDB Data Team • 09/28/2024
The CVE-2016-5022 vulnerability represents a critical denial of service weakness affecting multiple F5 BIG-IP product lines including Local Traffic Manager, Analytics, Application Protection Manager, Application Security Manager, and various other modules. This vulnerability specifically targets systems where packet filtering is enabled on virtual servers and self IP addresses, creating a pathway for remote attackers to exploit the Traffic Management Microkernel component. The affected versions span across multiple major releases including 11.2.x through 12.0.0, with specific hotfix requirements for each version line. The vulnerability operates by processing crafted network traffic that triggers an unexpected restart of the Traffic Management Microkernel, effectively disrupting service availability for legitimate users. This issue falls under the CWE-121 category of Stack-based Buffer Overflow and aligns with ATT&CK technique T1499.002 for Network Denial of Service attacks, making it particularly dangerous in enterprise environments where F5 BIG-IP appliances serve as critical infrastructure components.
The technical exploitation of this vulnerability occurs when malicious network packets are crafted to specifically target the packet filtering mechanisms within the Traffic Management Microkernel. The flaw manifests as a result of insufficient input validation and memory management within the microkernel's processing routines, allowing attackers to send specially constructed packets that cause the system to crash and restart. This behavior creates an automatic recovery loop that can be sustained by attackers, leading to prolonged service disruption. The vulnerability's impact extends beyond simple denial of service as it may potentially allow for additional unspecified impacts, suggesting possible privilege escalation or information disclosure scenarios. The attack vector is entirely remote and requires no authentication, making it particularly dangerous in environments where F5 appliances are exposed to untrusted network traffic. Network administrators should note that the vulnerability affects both virtual servers and self IP addresses, indicating a broad scope of potential attack surfaces within F5 BIG-IP deployments.
The operational impact of CVE-2016-5022 can be severe for organizations relying on F5 BIG-IP appliances for their network infrastructure. The Traffic Management Microkernel restart causes complete service interruption for applications and services that depend on these appliances, potentially affecting thousands of users simultaneously. Organizations may experience significant downtime, revenue loss, and potential customer dissatisfaction when such attacks occur. The vulnerability's presence in multiple product lines including APM, ASM, GTM, and various other modules means that the attack surface is extensive, requiring comprehensive patch management across the entire F5 ecosystem. Security teams must also consider that this vulnerability can be exploited in conjunction with other attack methods, potentially allowing for more sophisticated multi-stage attacks. The automatic restart behavior of the microkernel creates a challenging environment for forensic analysis and incident response, as the system state may be lost during the recovery process, complicating root cause analysis efforts.
Mitigation strategies for CVE-2016-5022 primarily focus on applying the appropriate vendor patches and hotfixes to all affected versions of F5 BIG-IP products. Organizations should prioritize patching their systems according to the vendor's recommended hotfix schedules, with particular attention to the specific version requirements mentioned in the vulnerability description. Network administrators should consider implementing additional security controls such as rate limiting, packet filtering at the network perimeter, and monitoring for unusual traffic patterns that may indicate exploitation attempts. The ATT&CK framework suggests implementing network segmentation and access control measures to limit the potential impact of such vulnerabilities. Organizations should also review their network architecture to minimize exposure of F5 appliances to untrusted networks and consider disabling packet filtering on virtual servers when it is not strictly required. Regular vulnerability assessments and security audits should be conducted to ensure that all F5 components are properly updated and that no additional vulnerabilities exist within the network infrastructure. The implementation of intrusion detection systems and network monitoring solutions can help detect exploitation attempts and provide early warning of potential attacks targeting this vulnerability.