CVE-2022-22247 in Junos OS Evolved
Summary
by MITRE • 10/18/2022
An Improper Input Validation vulnerability in ingress TCP segment processing of Juniper Networks Junos OS Evolved allows a network-based unauthenticated attacker to send a crafted TCP segment to the device, triggering a kernel panic, leading to a Denial of Service (DoS) condition. Continued receipt and processing of this TCP segment could create a sustained Denial of Service (DoS) condition. This issue affects Juniper Networks Junos OS Evolved: 21.3 versions prior to 21.3R3-EVO; 21.4 versions prior to 21.4R2-EVO; 22.1 versions prior to 22.1R2-EVO. This issue does not affect Juniper Networks Junos OS Evolved versions prior to 21.3R1-EVO.
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Analysis
by VulDB Data Team • 10/18/2022
The vulnerability identified as CVE-2022-22247 represents a critical improper input validation flaw within the ingress TCP segment processing functionality of Juniper Networks Junos OS Evolved operating systems. This weakness specifically targets the kernel-level processing of TCP packets, creating a pathway for malicious actors to exploit the system's network stack implementation. The vulnerability exists in the manner in which the operating system validates and processes incoming TCP segments, failing to properly sanitize or validate the structure and content of these network packets before kernel-level processing occurs. This design flaw enables an unauthenticated attacker positioned on the network to craft and transmit specifically formatted TCP segments that will trigger unexpected behavior within the kernel.
The technical exploitation of this vulnerability occurs through the careful construction of TCP segments that, when processed by the affected Junos OS Evolved versions, cause the kernel to enter an unrecoverable panic state. This kernel panic represents a fundamental system failure that results in immediate service disruption and requires system restart to restore normal operations. The vulnerability affects specific release branches of Juniper's Evolved operating system, including versions 21.3 prior to 21.3R3-EVO, 21.4 prior to 21.4R2-EVO, and 22.1 prior to 22.1R2-EVO, while older versions remain unaffected. The impact extends beyond simple service interruption as continued processing of malicious TCP segments can maintain sustained denial of service conditions, effectively keeping the target device in a perpetual state of kernel panic until manual intervention occurs.
From an operational perspective, this vulnerability presents a significant risk to network infrastructure reliability and availability, particularly for organizations relying on Juniper networking equipment for critical communications. The unauthenticated nature of the attack means that any network entity can potentially exploit this weakness without requiring prior access credentials or privileged information, making it particularly dangerous in environments where network segmentation is insufficient. The vulnerability directly maps to CWE-20, Improper Input Validation, which is classified as a fundamental weakness in software design that allows malformed inputs to cause unexpected behavior. This weakness is further categorized under the ATT&CK framework as part of the Defense Evasion and Resource Hijacking tactics, where adversaries can leverage system-level vulnerabilities to consume resources and disrupt normal operations.
Organizations affected by this vulnerability should prioritize immediate remediation through the application of available security patches from Juniper Networks, specifically targeting the versions mentioned in the advisory. The mitigation strategy should include implementing network segmentation to limit exposure, deploying intrusion detection systems to monitor for suspicious TCP traffic patterns, and establishing robust monitoring procedures to detect kernel panic events. Additionally, network administrators should consider implementing TCP sequence number randomization and other TCP stack hardening measures to reduce the effectiveness of potential exploitation attempts. The vulnerability demonstrates the critical importance of proper input validation at all levels of network stack implementation and underscores the need for comprehensive security testing of kernel-level components in network infrastructure devices.