CVE-2021-29078 in RBK852
Summary
by MITRE • 03/23/2021
Certain NETGEAR devices are affected by command injection by an unauthenticated attacker. This affects RBK852 before 3.2.17.12, RBK853 before 3.2.17.12, RBK854 before 3.2.17.12, RBR850 before 3.2.17.12, RBS850 before 3.2.17.12, RBK752 before 3.2.17.12, RBK753 before 3.2.17.12, RBK753S before 3.2.17.12, RBK754 before 3.2.17.12, RBR750 before 3.2.17.12, and RBS750 before 3.2.17.12.
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Analysis
by VulDB Data Team • 04/04/2021
This vulnerability represents a critical command injection flaw in NETGEAR networking equipment that allows unauthenticated attackers to execute arbitrary commands on affected devices. The vulnerability affects multiple models within the RBK and RBR series routers, specifically those running firmware versions prior to 3.2.17.12. The flaw stems from inadequate input validation and sanitization in the device's web interface handling, where user-supplied data is directly incorporated into system commands without proper escaping or filtering mechanisms. This type of vulnerability falls under CWE-77 which specifically addresses command injection flaws where attacker-controllable data is used in command construction without proper validation.
The operational impact of this vulnerability is severe as it provides remote attackers with complete control over affected devices without requiring any authentication credentials. An attacker can leverage this vulnerability to execute arbitrary system commands, potentially leading to full device compromise, data exfiltration, or use of the device as a pivot point for further network infiltration. The vulnerability exists in the web administration interface where parameters are processed without adequate sanitization, allowing attackers to inject malicious commands that get executed by the underlying operating system. This creates a persistent backdoor capability that can be exploited for extended periods without detection.
From a cybersecurity perspective, this vulnerability aligns with ATT&CK technique T1059.001 which covers command and scripting interpreter execution. The attack chain typically involves initial reconnaissance to identify vulnerable devices followed by exploitation of the command injection vulnerability to gain remote code execution. The affected devices represent a significant attack surface as they are often deployed in residential and small office environments where network security monitoring may be limited. The vulnerability demonstrates poor security practices in input handling and highlights the importance of proper secure coding practices for network infrastructure devices.
Organizations should immediately implement mitigations including firmware updates to versions 3.2.17.12 or later, which contain patches addressing the command injection vulnerability. Network segmentation and access controls should be strengthened to limit exposure of these devices to untrusted networks. Additionally, continuous monitoring for suspicious network traffic patterns and unauthorized device access attempts should be implemented. The vulnerability underscores the critical importance of maintaining current firmware versions and conducting regular security assessments of network infrastructure equipment. Organizations should also consider implementing network access control measures and intrusion detection systems to identify potential exploitation attempts targeting these types of vulnerabilities.