CVE-2016-1270 in Junos
Summary
by MITRE
The rpd daemon in Juniper Junos OS before 12.1X44-D60, 12.1X46 before 12.1X46-D45, 12.1X47 before 12.1X47-D30, 12.3 before 12.3R9, 12.3X48 before 12.3X48-D20, 13.2 before 13.2R7, 13.2X51 before 13.2X51-D40, 13.3 before 13.3R6, 14.1 before 14.1R4, and 14.2 before 14.2R2, when configured with BGP-based L2VPN or VPLS, allows remote attackers to cause a denial of service (daemon restart) via a crafted L2VPN family BGP update.
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Analysis
by VulDB Data Team • 04/29/2019
The vulnerability identified as CVE-2016-1270 affects the rpd daemon in Juniper Junos OS versions prior to specific patch releases, representing a significant denial of service weakness that impacts network infrastructure critical to service providers and enterprises. This vulnerability specifically manifests when the routing protocol daemon is configured with BGP-based Layer 2 Virtual Private Network (L2VPN) or Virtual Private LAN Service (VPLS) functionality, creating a condition where malicious actors can exploit a flaw in the processing of L2VPN family BGP updates. The issue stems from inadequate input validation within the daemon's handling of these specific BGP messages, allowing crafted malformed updates to trigger unexpected behavior in the routing process.
The technical flaw resides in the rpd daemon's insufficient validation mechanisms when processing BGP updates containing L2VPN family information, which falls under the Common Weakness Enumeration category 20 as it represents an input validation error. When the daemon receives a specially crafted BGP update message with malformed L2VPN attributes, it fails to properly handle the data structure, leading to a crash or restart of the routing protocol daemon. This behavior aligns with attack patterns documented in the MITRE ATT&CK framework under the T1499.004 technique for network denial of service attacks. The vulnerability specifically targets the BGP routing process within Juniper's networking equipment, where the daemon's failure to validate incoming L2VPN BGP updates results in a complete restart of the routing process, effectively causing a denial of service condition that impacts network connectivity and service availability.
The operational impact of this vulnerability extends beyond simple service disruption, as it can lead to cascading failures within network infrastructure where BGP-based L2VPN or VPLS services are critical for maintaining connectivity between remote sites. Network administrators may experience unexpected downtime, service interruptions, and potential loss of connectivity for customers relying on these services, particularly in enterprise environments where these routing protocols are fundamental to network operations. The vulnerability affects multiple Juniper Junos OS versions, indicating a widespread exposure across different release branches, making it particularly dangerous as organizations with diverse network equipment may simultaneously face this risk. The daemon restart caused by this vulnerability can result in temporary network outages, disruption of customer services, and potential financial losses for organizations dependent on continuous network availability.
Mitigation strategies for CVE-2016-1270 require immediate implementation of software updates and patches provided by Juniper to address the specific validation flaw in the rpd daemon's handling of L2VPN family BGP updates. Organizations should prioritize upgrading their Junos OS versions to the patched releases mentioned in the vulnerability description, particularly focusing on the specific version ranges where the vulnerability exists. Network administrators should also implement monitoring solutions to detect unusual BGP update patterns that might indicate exploitation attempts, and consider implementing access control measures to limit BGP peer relationships to trusted sources only. Additionally, implementing redundant routing protocols and failover mechanisms can help minimize the impact of potential exploitation, while maintaining network availability during patch deployment processes. The vulnerability serves as a reminder of the importance of regular security updates and proper input validation in network infrastructure software, as highlighted by industry best practices in cybersecurity governance and compliance standards.