CVE-2019-6971 in WR1043ND V2
Summary
by MITRE
An issue was discovered on TP-Link TL-WR1043ND V2 devices. An attacker can send a cookie in an HTTP authentication packet to the router management web interface, and fully control the router without knowledge of the credentials.
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Analysis
by VulDB Data Team • 10/15/2024
The vulnerability identified as CVE-2019-6971 affects TP-Link TL-WR1043ND V2 wireless routers, representing a critical authentication bypass flaw that undermines the security posture of network infrastructure devices. This vulnerability resides within the web management interface of the affected router model, specifically in how it handles HTTP authentication mechanisms. The issue manifests when an attacker can manipulate cookie values within HTTP authentication packets to gain unauthorized administrative access to the router's management interface without requiring legitimate credentials. This type of vulnerability falls under CWE-287 which addresses improper authentication issues, and aligns with ATT&CK technique T1078.004 for valid accounts and T1078.002 for single sign-on, as it exploits weaknesses in authentication mechanisms to achieve persistent access.
The technical implementation of this vulnerability stems from inadequate validation of authentication tokens within the router's web interface. When users attempt to access the router's management console, the system should properly verify authentication credentials through secure token validation mechanisms. However, the TL-WR1043ND V2 firmware fails to adequately validate the integrity and authenticity of cookies sent during the authentication process, allowing attackers to craft malicious cookie values that bypass the normal authentication flow. This flaw represents a fundamental breakdown in the authentication architecture, where the system accepts manipulated cookie values as legitimate authentication tokens, effectively rendering the password protection mechanism ineffective.
The operational impact of CVE-2019-6971 extends beyond simple unauthorized access, as it provides attackers with complete administrative control over the affected router. Once an attacker successfully exploits this vulnerability, they can modify router configurations, change network settings, implement malicious DNS redirects, install backdoors, or even create captive portals to capture network traffic. The implications are particularly severe because routers serve as central network control points, and compromising their management interfaces allows attackers to potentially gain access to entire internal networks. This vulnerability affects not only the device itself but also all devices connected to the network, as the attacker can modify firewall rules, DNS settings, and routing configurations to redirect traffic or establish persistent access points.
Mitigation strategies for this vulnerability require immediate firmware updates from TP-Link, as the issue stems from software implementation flaws within the router's web interface code. Network administrators should also implement additional security controls including network segmentation to isolate management interfaces, disable unnecessary web management access, and deploy intrusion detection systems to monitor for suspicious authentication attempts. The vulnerability highlights the importance of proper input validation and authentication token handling in embedded network devices, aligning with security best practices outlined in NIST SP 800-53 and ISO 27001 standards. Organizations should also consider implementing network access control measures and regularly auditing router configurations to detect unauthorized modifications that may result from exploitation of this vulnerability.