CVE-2025-70239 in DIR-513
Summary
by MITRE • 03/03/2026
Stack buffer overflow vulnerability in D-Link DIR-513 v1.10 via the curTime parameter to goform/formSetWAN_Wizard55.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 03/10/2026
The CVE-2025-70239 vulnerability represents a critical stack buffer overflow flaw discovered in D-Link DIR-513 router firmware version 1.10. This vulnerability specifically manifests within the web interface handling of the goform/formSetWAN_Wizard55 endpoint, which processes the curTime parameter. The flaw arises from insufficient input validation and bounds checking when processing user-supplied data through the web administration interface, creating a potential pathway for arbitrary code execution or system compromise. The vulnerability is particularly concerning as it affects a widely deployed consumer and small office networking device that serves as a primary gateway for internet connectivity in numerous households and businesses.
The technical implementation of this buffer overflow occurs when the router's web server receives a malformed curTime parameter value through the specified form endpoint. The device fails to properly validate the length of input data before copying it into a fixed-size stack buffer, allowing an attacker to overwrite adjacent memory locations. This memory corruption can potentially overwrite return addresses, function pointers, or other critical control data structures, enabling attackers to redirect execution flow or inject malicious code. The vulnerability falls under CWE-121 stack-based buffer overflow, which is classified as a high-severity issue in the Common Weakness Enumeration catalog due to its potential for remote code execution and system compromise.
The operational impact of this vulnerability extends beyond simple denial of service scenarios, as it creates opportunities for attackers to gain unauthorized access to network infrastructure. An attacker could exploit this vulnerability remotely through the web interface without requiring authentication, potentially leading to complete system compromise, data exfiltration, or the ability to establish persistent access points within the network. The affected D-Link DIR-513 device serves as a critical network gateway, making successful exploitation particularly dangerous for both individual users and enterprise environments. This vulnerability aligns with ATT&CK technique T1210 exploitation of remote services, where attackers target network devices to establish footholds within networks.
Mitigation strategies for CVE-2025-70239 should prioritize immediate firmware updates from D-Link, as the vendor has likely released patches addressing this specific buffer overflow. Network administrators should implement network segmentation and access controls to limit exposure of affected devices to untrusted networks. Additional protective measures include disabling unnecessary web interfaces, implementing intrusion detection systems to monitor for exploitation attempts, and conducting regular security assessments of network infrastructure. The vulnerability demonstrates the importance of proper input validation and memory safety practices in embedded networking devices, highlighting the need for comprehensive security testing of firmware components. Organizations should also consider network monitoring solutions that can detect anomalous behavior patterns associated with exploitation attempts against known vulnerable endpoints.