CVE-2019-0074 in Junos
Summary
by MITRE
A path traversal vulnerability in NFX150 Series and QFX10K Series, EX9200 Series, MX Series and PTX Series devices with Next-Generation Routing Engine (NG-RE) allows a local authenticated user to read sensitive system files. This issue only affects NFX150 Series and QFX10K Series, EX9200 Series, MX Series and PTX Series with Next-Generation Routing Engine (NG-RE) which uses vmhost. This issue affects Juniper Networks Junos OS on NFX150 Series and QFX10K, EX9200 Series, MX Series and PTX Series with NG-RE and vmhost: 15.1F versions prior to 15.1F6-S12 16.1 versions starting from 16.1R6 and later releases, including the Service Releases, prior to 16.1R6-S6, 16.1R7-S3; 17.1 versions prior to 17.1R3; 17.2 versions starting from 17.2R1-S3, 17.2R3 and later releases, including the Service Releases, prior to 17.2R3-S1; 17.3 versions starting from 17.3R1-S1, 17.3R2 and later releases, including the Service Releases, prior to 17.3R3-S3; 17.4 versions starting from 17.4R1 and later releases, including the Service Releases, prior to 17.4R1-S6, 17.4R2-S2, 17.4R3; 18.1 versions prior to 18.1R2-S4, 18.1R3-S3; 18.2 versions prior to 18.2R2; 18.2X75 versions prior to 18.2X75-D40; 18.3 versions prior to 18.3R1-S2, 18.3R2; 18.4 versions prior to 18.4R1-S1, 18.4R2. This issue does not affect: Juniper Networks Junos OS 15.1 and 16.2.
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Analysis
by VulDB Data Team • 01/07/2024
This vulnerability represents a path traversal flaw that specifically targets Juniper Networks routing devices equipped with Next-Generation Routing Engine (NG-RE) and vmhost functionality. The issue affects a broad range of enterprise networking hardware including NFX150 Series and QFX10K Series, EX9200 Series, MX Series and PTX Series devices. The vulnerability stems from insufficient input validation in the system's file access mechanisms, allowing authenticated local users to bypass normal file access controls and read arbitrary system files. This type of vulnerability falls under the Common Weakness Enumeration category CWE-22, which specifically addresses path traversal attacks where attackers can manipulate file paths to access unauthorized resources. The flaw is particularly concerning because it requires only local authentication, meaning an attacker who has already gained access to a device through legitimate means can escalate their privileges to access sensitive system information.
The technical implementation of this vulnerability involves the manipulation of file path references within the NG-RE subsystem that utilizes vmhost for virtual machine hosting capabilities. When legitimate users attempt to access system files through specific interfaces or commands, the system fails to properly sanitize input parameters that control file access paths. This allows an authenticated user to construct malicious file paths that traverse the filesystem hierarchy to access sensitive configuration files, log files, or other system resources that should remain protected. The vulnerability is specifically tied to the vmhost implementation within the NG-RE architecture, which provides virtualization capabilities for routing functions. Attackers can exploit this weakness to potentially extract cryptographic keys, configuration data, or other sensitive information that could be used for further attacks or system compromise. The impact is significant as it could lead to complete system compromise if attackers can access critical system files or credentials stored within the affected devices.
From an operational perspective, this vulnerability creates a serious risk for network infrastructure security as it allows attackers with local access to escalate their privileges and access sensitive system information. The affected devices typically operate in critical network environments where they handle routing decisions, security policies, and network traffic management. If an attacker gains local access through legitimate means such as administrative credentials or compromised accounts, they can exploit this vulnerability to extract confidential information that could be used for lateral movement within the network or to launch more sophisticated attacks. The vulnerability affects multiple software versions across different Junos OS releases, making it widespread across the Juniper product line. Organizations running these affected versions are at risk of information disclosure attacks that could expose network configuration details, authentication credentials, or other sensitive operational data. The fact that this affects multiple series of devices including enterprise routers, switches, and security appliances means that the potential attack surface is extensive.
Mitigation strategies for this vulnerability primarily involve applying the appropriate software patches and updates released by Juniper Networks. Organizations should immediately upgrade their affected devices to the patched versions specified in the advisory, paying particular attention to the version-specific requirements for each software release line. The affected versions span multiple major releases including 15.1F, 16.1, 17.1, 17.2, 17.3, 17.4, 18.1, 18.2, 18.3, and 18.4, with specific service releases noted for each line. Network administrators should also implement additional security controls such as restricting local access to these devices, implementing strong authentication mechanisms, and monitoring for suspicious file access patterns. The vulnerability aligns with ATT&CK technique T1005 for Data from Local System, as it allows attackers to extract data from the compromised device. Additionally, this vulnerability could enable privilege escalation and information gathering activities that might lead to further compromise through techniques such as T1078 for Valid Accounts or T1566 for Phishing. Organizations should also consider implementing network segmentation and access controls to limit the potential impact of local access compromises, ensuring that even if an attacker gains local access, they cannot easily move laterally through the network infrastructure.