CVE-2020-24550 in Find
Summary
by MITRE • 04/01/2021
An Open Redirect vulnerability in EpiServer Find before 13.2.7 allows an attacker to redirect users to untrusted websites via the _t_redirect parameter in a crafted URL, such as a /find_v2/_click URL.
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Analysis
by VulDB Data Team • 04/07/2021
The Open Redirect vulnerability identified as CVE-2020-24550 affects EpiServer Find versions prior to 13.2.7, representing a critical security flaw that enables attackers to manipulate user navigation through maliciously crafted URLs. This vulnerability specifically targets the _t_redirect parameter within the /find_v2/_click endpoint, creating a pathway for malicious redirection that can be exploited in various phishing and social engineering attacks. The flaw exists in the application's handling of redirect parameters without proper validation or sanitization of input values, allowing unauthorized redirection to external domains.
The technical implementation of this vulnerability stems from insufficient input validation within the EpiServer Find application's redirect mechanism. When users encounter search results or click on links within the EpiServer Find interface, the application processes the _t_redirect parameter to determine where to redirect users after certain actions. Attackers can manipulate this parameter to point to malicious websites, bypassing normal security controls that would typically prevent such redirections. This vulnerability falls under CWE-601, which specifically addresses Open Redirect vulnerabilities where web applications redirect users to external sites without proper validation. The flaw demonstrates a lack of proper security controls in parameter validation and input sanitization, creating an attack surface that can be exploited through simple URL manipulation.
The operational impact of this vulnerability extends beyond simple redirection, as it can be leveraged in sophisticated phishing campaigns and credential theft operations. When users click on malicious links that exploit this vulnerability, they may be redirected to attacker-controlled websites that mimic legitimate services, potentially capturing login credentials or other sensitive information. The vulnerability is particularly dangerous in enterprise environments where EpiServer Find is used for content management and search functionality, as it can be used to compromise user sessions and escalate privileges within the application ecosystem. Security researchers have noted that this type of vulnerability can be combined with other attack vectors to create more sophisticated multi-stage attacks, making it a significant concern for organizations relying on EpiServer Find for their digital platforms.
Organizations should implement immediate mitigations including updating to EpiServer Find version 13.2.7 or later, which contains the necessary patches to address the redirect parameter validation issue. Additional protective measures include implementing strict input validation for all redirect parameters, deploying web application firewalls to monitor and block suspicious redirect patterns, and conducting regular security assessments of all web applications that utilize redirect functionality. The vulnerability aligns with ATT&CK technique T1566, which covers social engineering tactics, specifically focusing on the use of malicious links to redirect users to compromised websites. Organizations should also consider implementing browser-based security controls such as Content Security Policy headers and redirect tracking mechanisms to detect and prevent unauthorized redirection attempts. Regular security training for personnel and monitoring of application logs for unusual redirect patterns can help identify potential exploitation attempts before they result in successful attacks.