CVE-2016-7474 in BIG-IP
Summary
by MITRE
In some cases the MCPD binary cache in F5 BIG-IP devices may allow a user with Advanced Shell access, or privileges to generate a qkview, to temporarily obtain normally unrecoverable information.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 11/22/2022
The vulnerability identified as CVE-2016-7474 resides within the MCPD binary cache implementation of F5 BIG-IP devices, representing a significant information disclosure risk that exploits the device's privilege model and caching mechanisms. This weakness specifically affects systems where users possess Advanced Shell access rights or the ability to generate qkview diagnostic reports, creating a vector for unauthorized information recovery that should normally be protected from access. The vulnerability operates by leveraging the interaction between the MCPD service and its binary cache, which stores temporary runtime data and configuration elements that typically should remain inaccessible to unauthorized users. The MCPD service in F5 BIG-IP systems is responsible for managing the device's configuration and monitoring processes, and its binary cache mechanism maintains temporary copies of various system components that may contain sensitive operational data.
The technical flaw manifests when privileged users with Advanced Shell access or qkview generation capabilities can manipulate the MCPD binary cache to extract information that would normally be unrecoverable through standard access controls. This occurs because the cache mechanism does not properly enforce access restrictions on temporary binary data structures that may contain sensitive configuration parameters, session information, or other operational details that should remain protected. The vulnerability essentially creates a temporary information leak channel where cached binary data, which normally would be purged or protected after use, can be accessed by users with specific privilege levels. This exploitation pathway represents a violation of the principle of least privilege and demonstrates inadequate separation between different privilege levels within the device's security architecture.
The operational impact of CVE-2016-7474 extends beyond simple information disclosure, as the extracted data may include sensitive configuration parameters, system credentials, or operational details that could facilitate further attacks against the BIG-IP device or the broader network infrastructure it protects. Attackers who successfully exploit this vulnerability could potentially gain insights into the device's internal operations, network topology, or security configurations that would otherwise remain hidden. The temporal nature of this vulnerability means that the information disclosure occurs only during specific operational conditions when the MCPD cache is active, but this limited window still provides attackers with valuable data that can be used to plan more sophisticated attacks. The vulnerability particularly affects organizations that rely heavily on F5 BIG-IP appliances for load balancing and application delivery, as these devices often serve as critical network infrastructure components.
Organizations should implement immediate mitigations including restricting Advanced Shell access to only essential personnel, implementing stricter controls over qkview generation capabilities, and ensuring proper access logging and monitoring of privileged activities. The vulnerability aligns with CWE-200, which addresses information exposure, and represents a specific case of inadequate access control enforcement within system cache mechanisms. From an ATT&CK framework perspective, this vulnerability maps to techniques involving privilege escalation and credential access, as it allows attackers to obtain information that would normally be protected from access. System administrators should also consider implementing network segmentation and monitoring to detect unusual patterns of qkview generation or Advanced Shell usage that might indicate exploitation attempts. Regular security assessments and patch management processes should be prioritized to address this and similar cache-related vulnerabilities that could provide unauthorized access to sensitive system information.