CVE-2018-0029 in Junos
Summary
by MITRE
While experiencing a broadcast storm, placing the fxp0 interface into promiscuous mode via the 'monitor traffic interface fxp0' can cause the system to crash and restart (vmcore). This issue only affects Junos OS 15.1 and later releases, and affects both single core and multi-core REs. Releases prior to Junos OS 15.1 are unaffected by this vulnerability. Affected releases are Juniper Networks Junos OS: 15.1 versions prior to 15.1F6-S11, 15.1R4-S9, 15.1R6-S6, 15.1R7; 15.1X49 versions prior to 15.1X49-D140; 15.1X53 versions prior to 15.1X53-D59 on EX2300/EX3400; 15.1X53 versions prior to 15.1X53-D67 on QFX10K; 15.1X53 versions prior to 15.1X53-D233 on QFX5200/QFX5110; 15.1X53 versions prior to 15.1X53-D471, 15.1X53-D490 on NFX; 16.1 versions prior to 16.1R3-S8, 16.1R5-S4, 16.1R6-S1, 16.1R7; 16.2 versions prior to 16.2R1-S6, 16.2R2-S5, 16.2R3; 17.1 versions prior to 17.1R1-S7, 17.1R2-S7, 17.1R3; 17.2 versions prior to 17.2R1-S6, 17.2R2-S4, 17.2R3; 17.2X75 versions prior to 17.2X75-D90, 17.2X75-D110; 17.3 versions prior to 17.3R1-S4, 17.3R2; 17.4 versions prior to 17.4R1-S3, 17.4R2.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 04/06/2023
This vulnerability represents a critical denial of service condition in Juniper Networks Junos OS affecting multiple release branches including 15.1, 16.1, 16.2, 17.1, 17.2, and 17.3 versions. The flaw manifests specifically when the system experiences a broadcast storm and the fxp0 interface is placed into promiscuous mode through the monitor traffic interface command. This combination creates a scenario where the system becomes unstable and subsequently crashes with a vmcore dump, requiring a complete system restart to recover. The vulnerability is particularly concerning as it affects both single core and multi-core Routing Engines, indicating a fundamental issue in the network operating system's handling of interface monitoring commands during high network traffic conditions. The issue is classified under CWE-119 as it involves improper handling of memory access during network interface operations, potentially leading to system instability through buffer overflows or memory corruption.
The technical exploitation of this vulnerability requires specific conditions to be met including the presence of broadcast storms on the network and deliberate activation of promiscuous mode on the fxp0 interface. This attack vector aligns with ATT&CK technique T1499.001 which involves network disruption through broadcast storms and traffic manipulation. The vulnerability demonstrates a lack of proper bounds checking and resource management when processing network traffic in promiscuous mode, particularly in the context of broadcast storm conditions where network packets are handled in large volumes. The system's failure to properly manage memory allocation and packet processing during these conditions results in a crash state that requires system-level restart to restore normal operations. This represents a fundamental flaw in the Junos OS network stack implementation where monitoring commands do not properly account for extreme network conditions.
The operational impact of this vulnerability extends beyond simple service disruption as it can affect network availability and reliability in production environments. Organizations running affected Junos OS versions may experience unexpected outages during periods of high network traffic or when broadcast storms occur naturally. The vulnerability affects multiple Juniper hardware platforms including EX2300, EX3400, QFX10K, QFX5200, QFX5110, NFX, and various other devices, indicating a widespread issue across the Juniper product line. The fact that this issue affects both single and multi-core systems suggests that the root cause is in the software implementation rather than hardware-specific behavior, making the vulnerability more pervasive across different deployment scenarios. Network administrators must be aware that this vulnerability can be triggered without malicious intent, simply through normal network conditions that result in broadcast storms.
Mitigation strategies for this vulnerability primarily involve applying the appropriate software patches released by Juniper Networks. The affected versions require specific release updates including 15.1F6-S11, 15.1R4-S9, 15.1R6-S6, 15.1R7, and their corresponding releases for other version branches. Organizations should also implement operational controls such as avoiding the use of promiscuous mode monitoring during high network traffic periods or when broadcast storms are anticipated. Network administrators should consider implementing traffic shaping and broadcast storm prevention mechanisms to reduce the likelihood of triggering this condition. The vulnerability also highlights the importance of proper network monitoring and alerting systems to detect broadcast storm conditions before they can lead to system instability. Additionally, organizations should maintain robust backup and recovery procedures to minimize the impact of unexpected system restarts. Security teams should monitor for any potential exploitation attempts targeting this vulnerability and ensure that all network devices are kept up to date with the latest security patches as recommended by Juniper's security advisories.