CVE-2019-3404 in Router P0
Summary
by MITRE
By adding some special fields to the uri ofrouter app function, the user could abuse background app cgi functions withoutauthentication. This affects 360 router P0 and F5C.
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Analysis
by VulDB Data Team • 03/04/2020
The vulnerability identified as CVE-2019-3404 represents a critical authentication bypass flaw in 360 router firmware versions affecting models P0 and F5C. This issue stems from improper input validation within the router's web interface handling mechanism, specifically in how the system processes URI parameters and background application functions. The vulnerability allows attackers to manipulate the request URI by injecting specially crafted fields that can trigger backend CGI functions without requiring proper authentication credentials. This flaw essentially creates a backdoor pathway through which unauthorized users can access administrative functions that should normally be restricted to authenticated administrators. The technical implementation of this vulnerability demonstrates a classic case of insufficient access control validation where the router's authentication mechanism fails to properly verify user credentials before executing sensitive operations. The affected 360 router models P0 and F5C are particularly vulnerable because their firmware does not adequately sanitize input parameters passed through the URI, creating a direct path for privilege escalation attacks. This type of vulnerability is categorized under CWE-285 which specifically addresses insufficient authorization issues in software systems.
The operational impact of this vulnerability extends far beyond simple unauthorized access to router configuration settings. An attacker who successfully exploits CVE-2019-3404 can potentially gain complete administrative control over the affected router, enabling them to modify network configurations, change DNS settings, disable security features, and establish persistent access points within the network. The implications are particularly severe because routers serve as the primary gateway for network traffic, making this vulnerability a critical entry point for broader network compromise. Attackers could leverage this flaw to redirect traffic, monitor network communications, or even inject malicious content into the network. The vulnerability's exploitation requires minimal technical skill, as it involves simple URI manipulation rather than complex attack vectors, making it particularly dangerous for widespread exploitation. According to ATT&CK framework, this vulnerability maps to T1078 which covers valid accounts and T1021 which covers remote services, as the attacker can essentially use the router's own administrative functions against itself. The lack of authentication enforcement creates a persistent threat vector that remains active as long as the vulnerable firmware version is installed on the device.
Mitigation strategies for CVE-2019-3404 should focus on immediate firmware updates provided by 360 to address the input validation and authentication bypass issues. Network administrators should also implement additional security measures including network segmentation, monitoring for unusual traffic patterns, and regular security audits of network devices. The vulnerability highlights the importance of proper input sanitization and authentication verification in web applications, particularly in embedded systems where security updates may be infrequent or delayed. Organizations should consider implementing network access control lists to limit access to router management interfaces and establish baseline configurations that disable unnecessary services. The incident underscores the critical need for secure coding practices and proper security testing of network devices before deployment. Regular vulnerability assessments and penetration testing should be conducted to identify similar authentication bypass vulnerabilities in other network infrastructure components. Additionally, network monitoring solutions should be configured to detect anomalous requests to router management interfaces, particularly those containing unusual parameter combinations that might indicate exploitation attempts. The vulnerability serves as a reminder that even consumer-grade networking equipment requires robust security measures to prevent unauthorized access to critical network infrastructure components.