CVE-2014-8014 in IOS XR
Summary
by MITRE
Cisco IOS XR allows remote attackers to cause a denial of service (RSVP process reload) via a malformed RSVP packet, aka Bug ID CSCub63710.
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Analysis
by VulDB Data Team • 06/16/2017
Cisco IOS XR operating systems contain a critical vulnerability in the Resource Reservation Protocol implementation that enables remote attackers to trigger a denial of service condition through carefully crafted malformed RSVP packets. This vulnerability specifically affects the RSVP process within the IOS XR framework and results in the complete reload of the affected process, disrupting network operations and potentially causing widespread service interruption across the affected infrastructure. The flaw exists in the packet processing logic where the system fails to properly validate incoming RSVP messages, allowing malicious actors to construct packets that contain malformed data structures or invalid field values that cause the RSVP daemon to crash and restart. The vulnerability is particularly concerning as it operates at the network control plane level, affecting the core routing and signaling functions that maintain network connectivity and traffic flow management. This issue impacts multiple Cisco IOS XR platform variants including routers running versions prior to the patched releases, making it a widespread concern for network administrators managing large-scale service provider networks.
The technical exploitation of this vulnerability requires an attacker to send specifically crafted RSVP packets to the target device without requiring any authentication credentials or privileged access. The malformed packets exploit a buffer handling flaw in the RSVP message parser where insufficient input validation allows the system to process invalid data structures that ultimately cause memory corruption and process termination. This type of vulnerability aligns with CWE-129, which describes improper validation of input ranges, and CWE-787, which covers out-of-bounds write operations that can occur when processing malformed network packets. The attack vector operates over the standard RSVP protocol ports and uses the existing network connectivity to reach the target device, making it particularly dangerous as it can be executed from anywhere on the network without requiring physical access or elevated privileges.
The operational impact of this vulnerability extends beyond simple service disruption as it can affect the stability and reliability of critical network infrastructure that relies on RSVP for traffic engineering and Quality of Service management. When the RSVP process reloads, it temporarily removes the device from the routing protocol convergence process, potentially causing routing instabilities, traffic black holes, or temporary network outages that can affect multiple customers or services depending on the network topology. Network operators may experience cascading effects where the restart of one device's RSVP process triggers additional reloads in neighboring devices as the network attempts to re-establish routing information and signaling connections. The vulnerability can be particularly problematic in service provider environments where network reliability and uptime are critical for maintaining customer service levels and regulatory compliance requirements.
Organizations should implement immediate mitigations including applying the relevant Cisco security patches and updates that address the RSVP packet validation issues in the IOS XR software. Network segmentation and access control measures should be enhanced to limit exposure of affected devices to untrusted network segments, while implementing network monitoring solutions that can detect and alert on unusual RSVP packet patterns or traffic anomalies. Additional defensive measures include configuring rate limiting on RSVP traffic and implementing ingress filtering to prevent malformed packets from reaching vulnerable systems. From an operational perspective, network administrators should conduct thorough testing of patch deployments in non-production environments before applying updates to production systems to ensure no unintended side effects occur. The implementation of robust network monitoring and intrusion detection systems that can identify suspicious RSVP traffic patterns will provide early warning capabilities to detect potential exploitation attempts. Organizations should also develop incident response procedures that specifically address this vulnerability type, ensuring rapid response capabilities when similar denial of service conditions occur in their network infrastructure.