CVE-2021-21579 in iDRAC9
Summary
by MITRE • 08/03/2021
Dell EMC iDRAC9 versions prior to 4.40.40.00 contain an open redirect vulnerability. A remote unauthenticated attacker may exploit this vulnerability to redirect users to arbitrary web URLs by tricking the victim users to click on maliciously crafted links.
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Analysis
by VulDB Data Team • 08/07/2021
The vulnerability identified as CVE-2021-21579 affects Dell EMC iDRAC9 management interfaces running versions prior to 4.40.40.00, representing a critical open redirect flaw that enables unauthorized remote exploitation. This vulnerability resides within the web-based management interface of the iDRAC9 controller, which is commonly used for remote server administration and monitoring in enterprise data centers. The open redirect vulnerability allows an attacker to manipulate the redirection behavior of the management interface, potentially enabling various malicious activities including phishing attacks, credential theft, and further exploitation of the targeted systems.
The technical implementation of this vulnerability stems from insufficient input validation and sanitization within the iDRAC9 web application's redirect functionality. When processing user-supplied URLs for redirection purposes, the system fails to properly validate or sanitize the input parameters, allowing attackers to inject malicious URLs that will be processed and executed by the vulnerable interface. This flaw typically manifests in parameters that handle redirect destinations, where the application directly uses user-provided input without adequate security controls to prevent unauthorized redirection to external domains. The vulnerability is classified under CWE-601 as an open redirect vulnerability, which is categorized as a weakness in the web application's input validation mechanisms.
The operational impact of this vulnerability is significant for enterprise environments that rely on Dell EMC servers with iDRAC9 management interfaces. Remote unauthenticated attackers can leverage this flaw to craft malicious links that, when clicked by legitimate users, redirect them to attacker-controlled websites. This capability enables sophisticated social engineering attacks where users might be tricked into visiting malicious sites that appear to be legitimate system management interfaces. The attack vector is particularly dangerous because it requires no authentication credentials to exploit, making it accessible to any remote attacker with knowledge of the target system's management interface. This vulnerability can be exploited to harvest user credentials, deploy malware, or facilitate further attacks within the network perimeter.
Organizations should immediately implement mitigation strategies to address this vulnerability, beginning with the mandatory upgrade of all affected iDRAC9 controllers to version 4.40.40.00 or later, which contains the necessary security patches to prevent the open redirect behavior. Network administrators should also consider implementing additional monitoring controls to detect suspicious redirect patterns in web traffic and establish network-level restrictions to prevent access to known malicious domains. The mitigation approach aligns with ATT&CK technique T1566.001 which covers phishing with malicious links, and T1071.004 which involves application layer protocol: web protocols. Security teams should also conduct comprehensive vulnerability assessments to identify any other systems running vulnerable iDRAC9 versions and ensure proper network segmentation to limit the potential impact of successful exploitation attempts.