CVE-2012-1367 in IOS
Summary
by MITRE
The MallocLite implementation in Cisco IOS 12.0, 12.2, 15.0, 15.1, and 15.2 allows remote attackers to cause a denial of service (Route Processor crash) via a BGP UPDATE message with a modified local-preference (aka LOCAL_PREF) attribute length, aka Bug ID CSCtq06538.
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Analysis
by VulDB Data Team • 12/07/2021
The vulnerability described in CVE-2012-1367 represents a critical denial of service flaw within Cisco IOS routing software that affects multiple version branches including 12.0, 12.2, 15.0, 15.1, and 15.2. This issue specifically targets the MallocLite memory allocation implementation which is responsible for managing dynamic memory operations within the IOS operating system. The flaw manifests when the system processes BGP UPDATE messages containing malformed local-preference attributes, creating a condition where legitimate network traffic can trigger system instability. This vulnerability operates at the network protocol level and demonstrates how seemingly minor attribute modifications can lead to catastrophic system failures in enterprise networking equipment.
The technical root cause of this vulnerability stems from inadequate input validation within the BGP processing module of Cisco IOS. When a remote attacker crafts a BGP UPDATE message with a modified LOCAL_PREF attribute length, the MallocLite implementation fails to properly handle the malformed data structure during memory allocation operations. This leads to memory corruption conditions that ultimately result in a complete Route Processor crash, effectively rendering the affected router non-functional. The vulnerability specifically leverages buffer overflow conditions in the memory management subsystem where the system attempts to allocate memory blocks based on the manipulated attribute length values. This represents a classic example of improper input validation and memory handling that falls under CWE-129, which addresses insufficient validation of length of input buffers, and CWE-125, which covers out-of-bounds read conditions.
The operational impact of this vulnerability extends beyond simple service disruption to potentially compromise entire network infrastructures. When a router becomes unresponsive due to this vulnerability, it can cause significant network partitioning and routing failures throughout the affected infrastructure. Network administrators may experience complete loss of connectivity to and from the compromised device, requiring manual intervention to restore normal operations through device rebooting. This type of attack can be particularly devastating in mission-critical environments where network availability is paramount for business operations. The vulnerability demonstrates how network protocols can be exploited to create cascading failures that propagate across interconnected systems, making it a serious concern for organizations relying on Cisco networking equipment for their infrastructure. The attack vector is particularly concerning as it requires only a single malformed BGP message to be received by the vulnerable device, making it easily exploitable by remote attackers without requiring authentication or privileged access.
Organizations affected by this vulnerability should implement immediate mitigations including applying the relevant Cisco security patches and updates that address the memory allocation handling in the MallocLite subsystem. Network segmentation strategies should be employed to isolate potentially vulnerable devices from external BGP peers until proper updates can be deployed. Implementing BGP message filtering and validation mechanisms can help prevent malformed UPDATE messages from reaching vulnerable routers, while monitoring systems should be configured to detect unusual routing behavior that might indicate exploitation attempts. The vulnerability also highlights the importance of network resilience planning and redundancy measures, as the impact of such a flaw can cascade across entire network domains. From an ATT&CK framework perspective, this vulnerability maps to techniques involving privilege escalation through protocol manipulation and resource exhaustion attacks, making it a significant concern for defensive security operations. Regular vulnerability assessments and network configuration reviews should be conducted to ensure that all network devices are properly patched and configured to prevent exploitation of similar memory handling flaws in the future.