CVE-2022-22193 in Junos OS
Summary
by MITRE • 04/14/2022
An Improper Handling of Unexpected Data Type vulnerability in the Routing Protocol Daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows a locally authenticated attacker with low privileges to cause a Denial of Service (DoS). Continued execution of this command might cause a sustained Denial of Service condition. If BGP rib sharding is configured and a certain CLI command is executed the rpd process can crash. During the rpd crash and restart, the routing protocols might be impacted and traffic disruption might be seen due to the loss of routing information. This issue affects: Juniper Networks Junos OS 20.3 versions prior to 20.3R3-S1; 20.4 versions prior to 20.4R3; 21.1 versions prior to 21.1R3; 21.2 versions prior to 21.2R2. Juniper Networks Junos OS Evolved 20.4 versions prior to 20.4R3-EVO; 21.1 versions prior to 21.1R3-EVO; 21.2 versions prior to 21.2R2-EVO. This issue does not affect: Juniper Networks Junos OS versions prior to 20.3R1. Juniper Networks Junos OS Evolved versions prior to 20.3R1-EVO.
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Analysis
by VulDB Data Team • 04/20/2022
The vulnerability described in CVE-2022-22193 represents a critical weakness in the Routing Protocol Daemon (rpd) component of Juniper Networks Junos OS and Junos OS Evolved platforms. This issue manifests as an improper handling of unexpected data types within the routing protocol processing mechanism, specifically affecting the BGP (Border Gateway Protocol) implementation. The vulnerability is particularly concerning because it can be exploited by locally authenticated attackers who possess only low privilege levels, making it accessible to users who should not have the ability to disrupt core network services. The flaw exists in the rpd process which manages routing information bases and handles BGP protocol operations, creating a potential attack surface that could compromise network availability.
The technical implementation of this vulnerability stems from inadequate input validation within the rpd daemon when processing specific CLI commands in environments where BGP rib sharding is configured. When a particular command is executed under these conditions, the rpd process experiences a crash due to improper data type handling that leads to memory corruption or unexpected behavior in the routing protocol processing pipeline. This type of vulnerability aligns with CWE-707, which covers improper handling of unexpected data types, and specifically relates to the broader category of improper input validation that can lead to process termination or system instability. The root cause involves the daemon's failure to properly sanitize or validate data types during command execution, particularly when dealing with routing information that may contain unexpected or malformed parameters.
The operational impact of this vulnerability extends beyond simple service disruption to potentially cause significant network-wide consequences. During the rpd crash and subsequent restart process, routing protocols experience temporary unavailability, leading to traffic disruption as routing information is lost and relearned. This disruption can result in packet loss, increased latency, and potential network partitions depending on the scale and criticality of the affected routing infrastructure. The sustained denial of service condition mentioned in the description indicates that repeated exploitation could maintain ongoing network instability, particularly in high-availability environments where routing stability is paramount. Network administrators may observe routing flapping, neighbor session instability, and overall degradation of network performance during the recovery period while the rpd process restarts and rebuilds its routing tables.
Organizations affected by this vulnerability should implement immediate mitigations including applying the vendor-provided patches and updates for the specific Junos OS versions mentioned in the advisory. The affected versions include various releases from 20.3 through 21.2, with specific service pack requirements that must be carefully reviewed and applied to prevent exploitation. Security teams should also consider implementing network segmentation and access controls to limit local authentication privileges where possible, reducing the attack surface for this specific vulnerability. Additionally, monitoring should be enhanced to detect unusual rpd process restarts or routing instability patterns that may indicate exploitation attempts. From an ATT&CK framework perspective, this vulnerability maps to T1499.004 (Endpoint Denial of Service) and potentially T1068 (Exploitation for Privilege Escalation) if the DoS conditions can be leveraged to gain additional privileges or if the disruption creates opportunities for further attacks. The vulnerability demonstrates the importance of proper input validation and error handling in network infrastructure software, as highlighted by the MITRE ATT&CK framework's emphasis on preventing process termination through proper software design practices.