CVE-2020-7997 in WRT-AC66U 3 RT
Summary
by MITRE
ASUS WRT-AC66U 3 RT 3.0.0.4.372_67 devices allow XSS via the Client Name field to the Parental Control feature.
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Analysis
by VulDB Data Team • 03/27/2024
The vulnerability identified as CVE-2020-7997 affects ASUS WRT-AC66U 3 RT 3.0.0.4.372_67 wireless routers and represents a cross-site scripting flaw within the parental control functionality. This issue resides in the Client Name field of the parental control feature, which fails to properly sanitize user input before processing and displaying it within the web interface. The vulnerability allows remote attackers to inject malicious scripts that execute in the context of other users' browsers when they view the parental control settings page. This particular implementation flaw demonstrates a classic lack of input validation and output encoding that enables persistent XSS attacks against authenticated users of the router's web management interface.
The technical exploitation of this vulnerability occurs through the manipulation of the Client Name field within the parental control configuration. When an attacker submits malicious script code through this field, the router fails to sanitize the input properly before storing and subsequently rendering it in the web interface. This creates a persistent XSS vector where the malicious payload executes whenever any user accesses the parental control section of the router's administration panel. The vulnerability is classified under CWE-79 as a failure to sanitize user input, specifically within the context of web application security. This flaw enables attackers to potentially steal session cookies, redirect users to malicious sites, or perform actions on behalf of authenticated users with the privileges of the router administrator.
The operational impact of CVE-2020-7997 extends beyond simple script injection as it compromises the integrity of the router's administrative interface and potentially exposes the entire network to further attacks. An attacker who successfully exploits this vulnerability could gain access to the router's administrative functions, modify network configurations, or establish persistent access points within the network. The attack vector requires no special privileges beyond access to the router's web interface, making it particularly dangerous as it can be exploited by anyone with knowledge of the router's IP address and basic authentication credentials. This vulnerability directly maps to attack techniques described in the MITRE ATT&CK framework under T1071.004 for application layer protocol usage and T1566 for credential access through social engineering. The compromised router could serve as a pivot point for lateral movement within the network, enabling attackers to target connected devices or escalate privileges to gain broader network access.
Mitigation strategies for CVE-2020-7997 should focus on immediate firmware updates from ASUS to address the specific XSS vulnerability in the parental control implementation. Network administrators should also implement additional security controls such as restricting access to the router's administrative interface to trusted IP addresses only, enabling strong authentication mechanisms, and monitoring for suspicious activity in the router's logs. Regular security assessments of network infrastructure should include vulnerability scanning for similar input validation flaws across all network devices. The implementation of web application firewalls and content security policies can provide additional protection layers against exploitation attempts. Organizations should also consider network segmentation to limit the potential impact of compromised devices and establish incident response procedures for addressing router-level security breaches. The vulnerability underscores the importance of proper input validation and output encoding in web applications, particularly in administrative interfaces where sensitive configuration data is handled.