CVE-2025-8137 in A702R
Summary
by MITRE • 07/25/2025
A vulnerability has been found in TOTOLINK A702R 4.0.0-B20230721.1521 and classified as critical. Affected by this vulnerability is an unknown functionality of the file /boafrm/formIpQoS of the component HTTP POST Request Handler. The manipulation of the argument mac leads to buffer overflow. The attack can be launched remotely. The exploit has been disclosed to the public and may be used.
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Analysis
by VulDB Data Team • 07/28/2025
The vulnerability identified as CVE-2025-8137 represents a critical buffer overflow flaw within the TOTOLINK A702R router firmware version 4.0.0-B20230721.1521. This issue resides in the HTTP POST Request Handler component, specifically affecting the /boafrm/formIpQoS file which processes incoming web requests. The vulnerability is particularly concerning as it allows remote exploitation without requiring any authentication or physical access to the device, making it highly accessible to threat actors. The flaw manifests when processing the mac argument parameter, which is commonly used for mac address identification within network management interfaces. This type of vulnerability falls under CWE-121, which describes stack-based buffer overflow conditions where insufficient bounds checking allows attackers to overwrite adjacent memory locations. The attack vector is classified as remote, meaning an attacker can exploit this vulnerability from outside the local network, potentially compromising the entire network infrastructure.
The technical exploitation of this buffer overflow vulnerability enables attackers to execute arbitrary code on the affected router through carefully crafted HTTP POST requests. The manipulation of the mac argument parameter allows for memory corruption that can be leveraged to overwrite critical program execution flow, potentially leading to complete system compromise. This vulnerability directly impacts the router's ability to process legitimate network management requests while simultaneously providing an attack surface for malicious actors to gain unauthorized control. The security implications extend beyond simple code execution as compromised routers can serve as entry points for broader network infiltration, DNS hijacking, or man-in-the-middle attacks against connected devices. The disclosed exploit demonstrates that this vulnerability has already been weaponized in the wild, indicating active exploitation attempts by threat actors.
The operational impact of CVE-2025-8137 is severe for organizations and individuals relying on TOTOLINK A702R routers, as the vulnerability can result in complete network compromise without any user interaction required. Network administrators face significant challenges in mitigating this issue since the router is typically deployed in residential or small office environments where firmware updates may not be regularly applied. The affected device's HTTP POST handler component represents a critical attack surface that, when compromised, can provide persistent access to network traffic and potentially enable lateral movement within the local network. This vulnerability aligns with ATT&CK technique T1059.007 for Command and Scripting Interpreter, as successful exploitation would allow attackers to execute commands on the compromised device. The potential for this vulnerability to be used as a foothold for broader network attacks makes it particularly dangerous in environments where network segmentation is not properly implemented.
Mitigation strategies for CVE-2025-8137 should include immediate firmware updates from TOTOLINK if available, network segmentation to isolate affected devices, and implementation of network monitoring to detect suspicious HTTP traffic patterns. Organizations should also consider disabling unnecessary web management interfaces and implementing firewall rules to restrict access to the router's management ports. The vulnerability's classification as critical by security vendors indicates that immediate action is required, as the public disclosure of exploit code increases the likelihood of widespread exploitation. Network administrators should also implement intrusion detection systems capable of identifying malformed HTTP POST requests targeting the specific vulnerable endpoint. Additionally, the use of network access control lists and regular security audits can help identify and remediate similar vulnerabilities in other network infrastructure components. This vulnerability serves as a reminder of the importance of maintaining current firmware versions and implementing robust network security practices to prevent exploitation of known vulnerabilities.