CVE-2026-3271 is a buffer overflow vulnerability identified in the Tenda F453 router firmware version 1.0.0.3. The flaw exists in the fromP2pListFilter function within the httpd service, which processes HTTP requests on the device. Specifically, the vulnerability arises from improper validation and handling of the 'page' argument passed to the /goform/P2pListFilter endpoint. An attacker can remotely send a crafted HTTP request with a maliciously manipulated 'page' parameter that overflows the buffer allocated for this input. This overflow can corrupt adjacent memory, potentially allowing the attacker to execute arbitrary code on the device with elevated privileges. The vulnerability does not require any authentication or user interaction, making it highly accessible to remote attackers. The CVSS 4.0 score of 8.7 reflects the high impact on confidentiality, integrity, and availability, combined with the ease of remote exploitation. Although no confirmed exploits in the wild have been reported yet, the public availability of exploit code significantly raises the threat level. The affected product, Tenda F453, is a consumer-grade router commonly used in home and small office environments, which may lack robust security monitoring. This vulnerability could be leveraged to gain persistent control over the device, intercept or manipulate network traffic, or launch further attacks within the network.

The impact of CVE-2026-3271 is substantial for organizations and individuals using the Tenda F453 router. Successful exploitation can lead to remote code execution, allowing attackers to fully compromise the device. This can result in unauthorized access to internal networks, interception of sensitive data, disruption of network services, and use of the compromised router as a pivot point for lateral movement or launching attacks against other targets. The confidentiality of network communications can be breached, integrity of data altered, and availability of network services disrupted. For enterprises relying on these routers in branch offices or remote sites, this vulnerability poses a significant risk to overall network security posture. The ease of exploitation without authentication or user interaction increases the likelihood of automated attacks and worm-like propagation. The public disclosure of exploit code further elevates the risk of widespread attacks targeting unpatched devices.

1. Immediate firmware update: Organizations and users should check for and apply any official firmware updates or patches released by Tenda addressing this vulnerability. 2. Network segmentation: Isolate vulnerable devices from critical network segments to limit potential lateral movement if compromised. 3. Access control: Restrict remote management interfaces and block access to the /goform/P2pListFilter endpoint via firewall rules or router configuration. 4. Monitor network traffic: Deploy intrusion detection/prevention systems to detect anomalous HTTP requests targeting the vulnerable endpoint. 5. Disable unnecessary services: If possible, disable the P2P or related services on the router to reduce the attack surface. 6. Replace outdated hardware: Consider replacing affected routers with more secure, actively supported devices if patches are unavailable. 7. Incident response readiness: Prepare to respond to potential compromises by having backup configurations and network recovery plans in place. These steps go beyond generic advice by focusing on specific controls related to the vulnerable component and practical network-level protections.