CVE-2025-6368 in DIR-619L
Summary
by MITRE • 06/21/2025
A vulnerability was found in D-Link DIR-619L 2.06B01. It has been rated as critical. This issue affects the function formSetEmail of the file /goform/formSetEmail. The manipulation of the argument curTime/config.smtp_email_subject leads to stack-based buffer overflow. The attack may be initiated 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 • 06/25/2025
The vulnerability identified as CVE-2025-6368 represents a critical stack-based buffer overflow flaw in D-Link DIR-619L router firmware version 2.06B01. This issue resides within the web-based management interface of the device, specifically in the formSetEmail function located at /goform/formSetEmail. The vulnerability stems from improper input validation of the curTime/config.smtp_email_subject parameter, which allows attackers to manipulate the argument in a manner that overflows the allocated stack buffer. Such buffer overflow conditions create opportunities for arbitrary code execution and system compromise, making this a particularly dangerous vulnerability in network infrastructure devices. The flaw's critical rating reflects its potential for remote exploitation without requiring authentication, enabling attackers to gain unauthorized control over the affected router.
The technical exploitation of this vulnerability follows a classic stack-based buffer overflow pattern that aligns with CWE-121, which describes stack-based buffer overflow conditions where insufficient bounds checking allows data to overwrite adjacent memory locations. Attackers can craft malicious input to the smtp_email_subject parameter that exceeds the allocated buffer space, causing a stack corruption that can be leveraged to redirect program execution flow. This type of vulnerability typically allows attackers to execute arbitrary code with the privileges of the web server process, which in router contexts often translates to full administrative control over the device. The remote exploitability aspect means that no physical access or local network presence is required for successful exploitation, making this vulnerability particularly concerning for widespread deployment.
The operational impact of CVE-2025-6368 extends beyond simple device compromise, as compromised routers can serve as persistent footholds for broader network attacks. Once exploited, the affected D-Link DIR-619L devices could be used to redirect network traffic, intercept communications, or serve as launching points for attacks against other networked systems. The fact that this vulnerability affects a device model that is no longer supported by the vendor significantly compounds the risk, as users cannot receive official security patches or updates to address the flaw. This scenario represents a classic case of legacy device vulnerability management where organizations must either replace the affected hardware or implement network segmentation and monitoring to mitigate exposure. The public disclosure of exploitation techniques further accelerates the threat landscape, as attackers can readily leverage existing proof-of-concept code to target vulnerable networks.
Security mitigations for this vulnerability must address both immediate remediation and long-term risk management strategies. The primary recommendation involves immediate replacement or decommissioning of all affected D-Link DIR-619L devices, as no vendor patches are available due to end-of-life status. Network segmentation should be implemented to isolate affected devices from critical network segments, while comprehensive network monitoring should be deployed to detect potential exploitation attempts or unauthorized access patterns. Organizations should also consider implementing intrusion detection systems that can identify malformed HTTP requests targeting the vulnerable formSetEmail endpoint. From an ATT&CK framework perspective, this vulnerability maps to techniques involving exploitation of remote services and privilege escalation, with potential lateral movement opportunities once initial compromise is achieved. The vulnerability's exploitation aligns with TTPs commonly associated with IoT device compromise and persistent network access, making comprehensive network hygiene and device inventory management essential components of the remediation strategy.