CVE-2020-3292 in RV016
Summary
by MITRE
Multiple vulnerabilities in the web-based management interface of Cisco Small Business RV320 and RV325 Series Routers and Cisco Small Business RV016, RV042, and RV082 Routers could allow an authenticated, remote attacker with administrative privileges to execute arbitrary code on an affected device. The vulnerabilities are due to insufficient boundary restrictions on user-supplied input to scripts in the web-based management interface. An attacker with administrative privileges that are sufficient to log in to the web-based management interface could exploit each vulnerability by sending crafted requests that contain overly large values to an affected device, causing a stack overflow. A successful exploit could allow the attacker to cause the device to crash or allow the attacker to execute arbitrary code with root privileges on the underlying operating system.
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Analysis
by VulDB Data Team • 10/25/2020
The vulnerability identified as CVE-2020-3292 affects Cisco Small Business routers including the RV320 and RV325 series as well as the RV016, RV042, and RV082 models. These devices operate with web-based management interfaces that provide administrative access to network configuration and monitoring capabilities. The vulnerability stems from insufficient input validation mechanisms within the web interface scripts, creating a pathway for malicious exploitation. This flaw represents a critical security weakness that could enable remote code execution when combined with administrative access, making it particularly dangerous for network infrastructure devices.
The technical flaw manifests as inadequate boundary checking on user-supplied input parameters within the web-based management interface scripts. When an authenticated attacker with administrative privileges submits crafted requests containing excessively large input values, the system fails to properly validate these inputs before processing them. This lack of proper input sanitization leads to stack overflow conditions within the affected software components. The stack overflow occurs because the system does not enforce size limits or boundary checks on input data, allowing maliciously crafted payloads to exceed allocated memory buffers and overwrite adjacent memory locations. This vulnerability directly maps to CWE-121 Stack-based Buffer Overflow, which is classified as a critical weakness in software security architecture.
The operational impact of this vulnerability is severe as it enables a successful attacker to achieve complete system compromise with root privileges. Once exploited, the attacker can cause the affected device to crash or more critically, execute arbitrary code with the highest level of system privileges available. This means the attacker gains complete control over the router's operating system, potentially allowing them to modify network configurations, intercept traffic, establish backdoors, or use the compromised device as a pivot point for attacks against other network segments. The vulnerability's remote execution capability combined with its requirement for only administrative credentials makes it particularly attractive to threat actors targeting network infrastructure.
Mitigation strategies for CVE-2020-3292 should focus on immediate patching of affected devices through official Cisco security updates. Organizations must ensure that all affected router models receive the latest firmware versions that address the input validation flaws. Network segmentation and access control measures should be implemented to limit administrative access to only necessary personnel and systems. Regular security audits of network devices should include verification of patch status and monitoring for unauthorized administrative access attempts. The vulnerability demonstrates the importance of implementing proper input validation and boundary checking mechanisms as outlined in the OWASP Top Ten security principles and aligns with ATT&CK technique T1059.007 for command and scripting interpreter, as attackers could leverage the executed code to establish persistent access. Additionally, network monitoring solutions should be configured to detect anomalous traffic patterns that might indicate exploitation attempts, particularly focusing on unusual request sizes or malformed inputs to web interfaces.