CVE-2025-9783 in A702R
Summary
by MITRE • 09/01/2025
A vulnerability was determined in TOTOLINK A702R 4.0.0-B20211108.1423. This issue affects the function sub_418030 of the file /boafrm/formParentControl. Executing manipulation of the argument submit-url can lead to buffer overflow. The attack may be launched remotely. The exploit has been publicly disclosed and may be utilized.
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Analysis
by VulDB Data Team • 09/01/2025
The vulnerability identified as CVE-2025-9783 represents a critical buffer overflow condition within the TOTOLINK A702R router firmware version 4.0.0-B20211108.1423. This flaw exists in the web management interface component located at /boafrm/formParentControl, specifically within the sub_418030 function that processes user input parameters. The affected parameter submit-url serves as the attack vector for this memory corruption vulnerability, which allows remote exploitation without requiring authentication. The buffer overflow occurs when the system fails to properly validate or limit the length of data provided through the submit-url argument, creating an opportunity for malicious actors to overwrite adjacent memory locations and potentially execute arbitrary code on the affected device.
This vulnerability falls under the CWE-121 category of stack-based buffer overflow, which is classified as a serious security weakness in software development practices. The attack surface is particularly concerning as it operates entirely through the web interface, making it accessible to remote attackers who can leverage this flaw from anywhere on the internet. The publicly disclosed exploit demonstrates that threat actors have already developed working tools to target this specific vulnerability, increasing the risk to affected users. The router's web management interface typically serves as the primary attack surface for network devices, making this flaw particularly dangerous as it could allow unauthorized individuals to gain full administrative control over the device.
The operational impact of this vulnerability extends beyond simple remote code execution to encompass complete device compromise and potential network infiltration. Once exploited, an attacker could gain persistent access to the router's administrative functions, enabling them to modify network configurations, redirect traffic, establish backdoors, or use the device as a pivot point for attacking other systems within the local network. The affected TOTOLINK A702R model represents a common consumer-grade router that many households and small businesses rely upon for network connectivity, making the potential for widespread exploitation significant. Network administrators and security professionals should be particularly concerned about the implications of this vulnerability, as compromised routers can serve as persistent threats within network infrastructure.
Mitigation strategies for CVE-2025-9783 should include immediate firmware updates from TOTOLINK if available, as the vendor has likely released patches to address this specific vulnerability. Network segmentation and firewall rules can help limit the potential impact of exploitation by restricting access to the router's web management interface from untrusted networks. Monitoring network traffic for suspicious activity related to the affected router model and implementing intrusion detection systems can help identify exploitation attempts. Additionally, organizations should consider disabling unnecessary web management interfaces and implementing strong authentication measures for any remaining access points. The vulnerability's classification under ATT&CK technique T1059.007 for scripting languages and T1021.001 for remote services indicates that attackers may leverage this access to establish persistent command and control capabilities within compromised networks. Regular security assessments and vulnerability scanning should be conducted to identify similar issues in other network infrastructure components, as this type of buffer overflow vulnerability often indicates broader software quality issues that may exist elsewhere in the system.