CVE-2024-0931 in AC10U
Summary
by MITRE • 01/26/2024
A vulnerability classified as critical was found in Tenda AC10U 15.03.06.49_multi_TDE01. This vulnerability affects the function saveParentControlInfo. The manipulation of the argument deviceId/time/urls leads to stack-based buffer overflow. The attack can be initiated remotely. The exploit has been disclosed to the public and may be used. The identifier of this vulnerability is VDB-252136. 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 • 02/19/2024
The vulnerability identified as CVE-2024-0931 represents a critical stack-based buffer overflow flaw within the Tenda AC10U router firmware version 15.03.06.49_multi_TDE01. This vulnerability specifically resides in the saveParentControlInfo function, which processes user input parameters including deviceId, time, and urls. The flaw arises from insufficient input validation and bounds checking within the firmware's network management interface, creating a pathway for malicious actors to execute arbitrary code through remote exploitation. The affected device operates under a web-based administrative interface that handles parental control configuration data, making this vulnerability particularly dangerous as it allows attackers to manipulate network access controls and potentially gain unauthorized access to connected devices. The stack-based buffer overflow occurs when the device processes malformed input data through the saveParentControlInfo function, causing memory corruption that can be leveraged to overwrite adjacent memory locations and potentially execute malicious code with elevated privileges.
The technical implementation of this vulnerability aligns with CWE-121 Stack-based Buffer Overflow, which occurs when a program writes data beyond the bounds of a fixed-length stack buffer, leading to memory corruption and potential code execution. The attack vector is remote, meaning an attacker can exploit this vulnerability without requiring physical access to the device, making it particularly concerning for network administrators and home users alike. The fact that the exploit has been publicly disclosed and is believed to be in active use significantly increases the risk profile of affected devices. The specific function saveParentControlInfo suggests this vulnerability impacts the router's parental control features, where users configure device access restrictions based on time schedules and URL filtering. When an attacker sends specially crafted data to this function through the web interface, the buffer overflow can be triggered, potentially allowing for complete device compromise and unauthorized network access.
The operational impact of CVE-2024-0931 extends beyond simple device compromise to encompass broader network security implications. Once an attacker successfully exploits this vulnerability, they can potentially gain full administrative control over the router, enabling them to modify network settings, redirect traffic, monitor network communications, and establish persistent access points. The parental control functionality becomes a vector for further exploitation, as attackers can manipulate access restrictions to bypass security measures or create backdoors for future access. This vulnerability particularly affects home networks and small office environments where Tenda AC10U devices are commonly deployed, potentially exposing sensitive personal data, corporate information, and connected IoT devices to unauthorized access. The lack of vendor response to early disclosure attempts compounds the issue, leaving users without official patches or mitigation guidance, which is characteristic of the ATT&CK technique T1210 Exploitation of Remote Services where adversaries leverage unpatched vulnerabilities in network services.
Mitigation strategies for CVE-2024-0931 should focus on immediate network isolation and firmware updates where available. Network administrators should implement network segmentation and firewall rules to limit access to affected devices, particularly restricting access to the administrative web interface from external networks. The most effective long-term solution involves updating to a patched firmware version from Tenda, though the vendor's lack of response means users may need to seek third-party firmware alternatives or consider device replacement. Additional protective measures include disabling unnecessary services, implementing strong authentication mechanisms, and monitoring network traffic for signs of exploitation attempts. Organizations should also consider network intrusion detection systems that can identify anomalous traffic patterns associated with buffer overflow exploitation attempts, as these systems can provide early warning of potential attacks. Given the public availability of the exploit and the critical severity classification, immediate action is recommended to prevent potential exploitation and maintain network integrity.