CVE-2024-4126 in W15E
Summary
by MITRE • 04/24/2024
A vulnerability was found in Tenda W15E 15.11.0.14 and classified as critical. This issue affects the function formSetSysTime of the file /goform/SetSysTimeCfg. The manipulation of the argument manualTime 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-261869 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 • 01/16/2025
The vulnerability identified as CVE-2024-4126 represents a critical stack-based buffer overflow flaw in the Tenda W15E 15.11.0.14 firmware, specifically within the formSetSysTime function located in the /goform/SetSysTimeCfg file. This issue stems from inadequate input validation of the manualTime parameter, which allows attackers to manipulate the system time settings through a web interface. The vulnerability's classification as critical indicates severe security implications that could compromise the entire network infrastructure. The stack-based buffer overflow occurs when the manualTime argument exceeds the allocated buffer space, potentially allowing arbitrary code execution through memory corruption. This flaw exists within the device's web management interface, making it accessible to remote attackers without requiring physical access or authentication credentials.
The technical exploitation of this vulnerability leverages the improper handling of user-supplied data within the SetSysTimeCfg form processing function. When the manualTime parameter is submitted through the web interface, the firmware fails to properly validate or sanitize the input before copying it into a fixed-size stack buffer. This oversight creates an exploitable condition where an attacker can craft malicious input that overflows the buffer and potentially overwrites adjacent memory locations including return addresses. The vulnerability's remote attack vector significantly amplifies its danger, as attackers can exploit this flaw from any location with network access to the device. The public disclosure of the exploit means that malicious actors can readily implement this attack without requiring advanced technical skills or proprietary knowledge, making this vulnerability particularly dangerous in environments where networked devices are exposed to untrusted networks.
The operational impact of CVE-2024-4126 extends beyond simple device compromise to potentially enable broader network infiltration and persistent access. Successful exploitation could allow attackers to execute arbitrary code with the privileges of the web server process, potentially leading to complete system takeover of the Tenda W15E device. This compromise could serve as a foothold for attackers to conduct lateral movement within the network, as the device may be used for routing, firewall management, or other critical network functions. The vulnerability affects the system time configuration which could be leveraged to disrupt network services, bypass time-based security controls, or interfere with logging mechanisms that depend on accurate timestamps. The lack of vendor response to early disclosure attempts creates a significant security gap, leaving users without official patches or mitigation guidance during the period when the exploit is publicly available.
Security professionals should implement immediate network segmentation measures to isolate affected devices from critical network segments, particularly those that do not require direct internet access. The recommended mitigation strategy includes disabling unnecessary web management interfaces, implementing firewall rules to restrict access to the device's management ports, and deploying network monitoring solutions to detect anomalous traffic patterns that might indicate exploitation attempts. Organizations should also consider deploying intrusion detection systems that can identify attempts to exploit known buffer overflow vulnerabilities in network infrastructure devices. The vulnerability aligns with CWE-121 stack-based buffer overflow and can be categorized under ATT&CK technique T1059.007 for command and scripting interpreter, potentially enabling privilege escalation through code execution. Given the public availability of the exploit and the vendor's lack of response, proactive network defense measures are essential to protect against potential compromise of these network devices.