CVE-2024-1000 in N200RE
Summary
by MITRE • 01/29/2024
A vulnerability was found in Totolink N200RE 9.3.5u.6139_B20201216. It has been rated as critical. This issue affects the function setTracerouteCfg of the file /cgi-bin/cstecgi.cgi. The manipulation of the argument command leads to stack-based buffer overflow. The attack may be initiated remotely. The exploit has been disclosed to the public and may be used. The identifier VDB-252269 was assigned to this vulnerability. NOTE: The vendor was contacted early about this disclosure but did not respond in any way.
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Analysis
by VulDB Data Team • 02/21/2024
The vulnerability identified as CVE-2024-1000 represents a critical stack-based buffer overflow flaw in the Totolink N200RE router firmware version 9.3.5u.6139_B20201216. This issue resides within the setTracerouteCfg function of the /cgi-bin/cstecgi.cgi web interface component, making it accessible through the device's web management interface. The vulnerability stems from inadequate input validation when processing the command argument, creating a condition where maliciously crafted input can exceed the bounds of a fixed-size stack buffer. This particular implementation flaw aligns with CWE-121 Stack-based Buffer Overflow, which is classified as a high-severity weakness in the CWE top 25 list. The attack vector is remote, meaning an unauthenticated attacker can exploit this vulnerability without requiring physical access to the device, making it particularly dangerous in networked environments.
The operational impact of this vulnerability extends beyond simple privilege escalation or denial of service scenarios. A successful exploitation could enable remote code execution on the affected router, providing attackers with complete control over the device's network functions and potentially allowing them to establish persistent backdoors. The stack-based buffer overflow creates an opportunity for attackers to overwrite critical memory locations including return addresses, function pointers, and other control data structures. This type of vulnerability can be leveraged for privilege escalation attacks and may allow threat actors to gain unauthorized access to the local network, redirect traffic, or even use the compromised device as a pivot point for attacking other systems within the network. The fact that this vulnerability has been publicly disclosed and has an assigned VDB identifier indicates that exploitation techniques are likely available in the wild, increasing the urgency for remediation.
Network security professionals should recognize this vulnerability as a significant threat to small office and home network environments where Totolink routers are commonly deployed. The exploitation of this flaw could lead to complete network compromise, especially in scenarios where the router serves as a gateway or firewall device. The vulnerability's classification as critical aligns with ATT&CK technique T1059.007 for Command and Scripting Interpreter and T1071.004 for Application Layer Protocol: DNS, as attackers could potentially manipulate network traffic and DNS resolution through compromised router functions. Organizations should immediately implement network segmentation and monitoring to detect anomalous traffic patterns that might indicate exploitation attempts. The lack of vendor response to early disclosure efforts compounds the risk, as users may not receive timely patches or firmware updates to address this critical security gap. Security teams should also consider implementing network access controls to limit exposure of affected devices and monitor for potential exploitation attempts through network traffic analysis and intrusion detection systems.
Mitigation strategies should include immediate firmware updates if available from the vendor, network segmentation to isolate affected devices, and comprehensive network monitoring for suspicious activities. Organizations should also implement network access controls to restrict access to the affected router's web interface and consider disabling unnecessary services. The vulnerability's remote exploitability makes it particularly dangerous, as attackers can target these devices from anywhere on the internet without requiring local network access. Security teams should conduct thorough vulnerability assessments of all network devices and implement continuous monitoring to detect potential exploitation attempts. Given the lack of vendor response, users may need to consider alternative security measures such as replacing affected hardware or implementing network-level protections to prevent exploitation attempts. The public disclosure of this vulnerability and its assigned VDB identifier indicates that security researchers and threat actors have already developed working exploit code, making immediate action essential to protect network infrastructure from potential compromise.