CVE-2025-7909 in DIR-513
Summary
by MITRE • 07/21/2025
A vulnerability was found in D-Link DIR-513 1.0. It has been rated as critical. Affected by this issue is the function sprintf of the file /goform/formLanSetupRouterSettings of the component Boa Webserver. The manipulation of the argument curTime leads to stack-based buffer overflow. The attack may be launched remotely. The exploit has been disclosed to the public and may be used. This vulnerability only affects products that are no longer supported by the maintainer.
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Analysis
by VulDB Data Team • 07/25/2025
The vulnerability CVE-2025-7909 represents a critical stack-based buffer overflow in the D-Link DIR-513 router model running firmware version 1.0. This flaw resides within the Boa web server component and specifically targets the sprintf function located in the /goform/formLanSetupRouterSettings file. The vulnerability is particularly concerning because it allows remote exploitation through manipulation of the curTime argument, which directly impacts the router's web interface functionality. The issue stems from improper input validation and buffer handling within the web server's processing logic, creating a pathway for attackers to execute arbitrary code on the affected device.
The technical exploitation of this vulnerability occurs through a stack-based buffer overflow condition that arises when the sprintf function processes the curTime parameter without adequate bounds checking. This type of vulnerability is classified as CWE-121, which specifically addresses stack-based buffer overflow conditions where insufficient boundary checking allows attackers to overwrite adjacent stack memory locations. The attack vector is remote, meaning an unauthenticated attacker can exploit this vulnerability from outside the network without requiring physical access or prior authentication to the device. The exploitation process typically involves crafting a malicious payload that exceeds the allocated buffer space, causing a stack overflow that can potentially be leveraged to execute arbitrary code with the privileges of the web server process.
The operational impact of this vulnerability extends beyond simple remote code execution, as it fundamentally compromises the security posture of the affected network infrastructure. Given that the D-Link DIR-513 is a consumer-grade router, this vulnerability creates a significant risk for home and small office networks where such devices often serve as the primary gateway to the internet. The exploit being publicly disclosed increases the likelihood of widespread exploitation, as malicious actors can readily develop automated tools to target vulnerable devices. This vulnerability particularly affects networks that rely on legacy router firmware, as the device is no longer supported by the vendor, meaning no security patches or updates are available to address the issue. The compromised router could serve as a persistent foothold for attackers to conduct further reconnaissance, establish command and control channels, or launch attacks against other devices within the network.
The lack of vendor support for the D-Link DIR-513 significantly compounds the severity of this vulnerability, as users cannot rely on official security updates to remediate the issue. This situation aligns with ATT&CK technique T1068, which describes the use of elevated privileges to gain access to systems, as the compromised router could provide attackers with network access that bypasses typical perimeter defenses. Organizations and individuals using this device should immediately implement network segmentation measures to isolate affected routers from critical systems, disable unnecessary services, and consider replacing the device with a supported model. The vulnerability also highlights the importance of firmware update management and the risks associated with using unsupported network equipment in production environments. Network administrators should monitor for signs of exploitation attempts and consider implementing intrusion detection systems to identify potential attacks targeting this specific vulnerability. Additionally, the incident underscores the need for proper security assessment of legacy network infrastructure and the establishment of protocols for identifying and addressing unsupported devices that may pose security risks to the broader network environment.