CVE-2021-22784 in C-Bus Toolkit
Summary
by MITRE • 07/21/2021
A CWE-306: Missing Authentication for Critical Function vulnerability exists in C-Bus Toolkit v1.15.8 and prior that could allow an attacker to use a crafted webpage to obtain remote access to the system.
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Analysis
by VulDB Data Team • 07/26/2021
The vulnerability identified as CVE-2021-22784 represents a critical authentication flaw classified under CWE-306, which specifically addresses missing authentication for critical functions. This weakness exists within the C-Bus Toolkit version 1.15.8 and earlier releases, creating a significant security risk for systems utilizing this software. The vulnerability stems from insufficient verification mechanisms that should be in place to authenticate users before granting access to sensitive system functions. Attackers can exploit this flaw by crafting malicious webpages that leverage the absence of proper authentication checks, potentially enabling unauthorized remote access to affected systems.
The technical implementation of this vulnerability allows threat actors to bypass normal authentication procedures through carefully constructed web content that manipulates the toolkit's access controls. This type of attack vector specifically targets the critical function access mechanisms within the C-Bus Toolkit, where legitimate authentication should be required but is instead omitted or improperly enforced. The flaw essentially creates a backdoor pathway that enables remote exploitation without the need for legitimate credentials, making it particularly dangerous for industrial control systems and building automation environments where such toolkits are commonly deployed.
From an operational standpoint, this vulnerability poses severe risks to organizations relying on C-Bus Toolkit for their building management and automation systems. The potential impact includes unauthorized access to critical infrastructure controls, data exfiltration, and possible system compromise that could affect building operations, security systems, and overall facility management. The remote nature of the attack means that adversaries can potentially exploit this vulnerability from anywhere on the internet without requiring physical access to the target systems, significantly expanding the attack surface and making detection more challenging.
Organizations should implement immediate mitigations including upgrading to the latest version of C-Bus Toolkit where the authentication flaw has been addressed. Network segmentation and access controls should be strengthened to limit exposure of affected systems to untrusted networks. Additionally, monitoring for suspicious web traffic and implementing intrusion detection systems can help identify potential exploitation attempts. The vulnerability aligns with ATT&CK technique T1190, which covers exploitation of remote services, and represents a clear violation of the principle of least privilege as defined in security frameworks. Security teams should also consider conducting thorough vulnerability assessments of their entire building automation ecosystem to identify other potential entry points that may present similar authentication weaknesses.