CVE-2025-15232 is a stack-based buffer overflow vulnerability identified in the Tenda M3 router firmware version 1.0.0.13(4903). The flaw exists in the function formSetAdPushInfo, specifically in the handling of the mac/terminal argument within the /goform/setAdPushInfo endpoint. An attacker can remotely send crafted requests to this endpoint, manipulating the argument to overflow the stack buffer. This overflow can overwrite the return address or other control data on the stack, enabling arbitrary code execution or causing a denial of service by crashing the device. The vulnerability requires no user authentication or interaction, and the attack vector is network-based, making it highly accessible to remote attackers. The CVSS 4.0 base score is 8.7, reflecting the high impact on confidentiality, integrity, and availability, combined with low attack complexity and no required privileges. Although no active exploitation has been reported, publicly available exploit code increases the risk of imminent attacks. The vulnerability affects a widely deployed consumer and small business router model, which often serves as a gateway device, making successful exploitation a critical threat to network security. The lack of an official patch at the time of disclosure necessitates immediate mitigation efforts to reduce exposure.

For European organizations, especially small and medium enterprises (SMEs) and home office users relying on Tenda M3 routers, this vulnerability poses significant risks. Successful exploitation can lead to full compromise of the router, allowing attackers to intercept, modify, or redirect network traffic, potentially leading to data breaches or lateral movement within corporate networks. The disruption or takeover of gateway devices can cause denial of service, impacting business continuity. Given the router's role as a network perimeter device, attackers could establish persistent footholds or launch further attacks against internal systems. The vulnerability's remote exploitability without authentication increases the attack surface, particularly in environments where routers are exposed to the internet or poorly segmented networks. This threat could also affect managed service providers supporting multiple clients using this hardware, amplifying the potential impact across sectors. The availability of exploit code raises the likelihood of exploitation attempts, necessitating urgent attention to mitigate risks.

1. Immediate network-level controls: Restrict access to the router's management interfaces by implementing firewall rules to block inbound traffic to the /goform/setAdPushInfo endpoint from untrusted networks, especially the internet. 2. Network segmentation: Isolate Tenda M3 routers from critical internal networks to limit the impact of a compromised device. 3. Monitor network traffic for anomalous requests targeting the vulnerable endpoint, using intrusion detection/prevention systems (IDS/IPS) with custom signatures. 4. Disable remote management features if not required, reducing exposure to remote attacks. 5. Regularly audit and inventory network devices to identify all Tenda M3 routers running the affected firmware version. 6. Apply firmware updates promptly once the vendor releases a patch addressing CVE-2025-15232. 7. Employ strong network access controls and consider replacing vulnerable devices with models from vendors with robust security track records if patches are delayed. 8. Educate users and administrators about the risks and signs of exploitation to enable rapid incident response.