CVE-2025-70250 Overview
A stack buffer overflow vulnerability has been identified in D-Link DIR-513 firmware version 1.10. The vulnerability exists in the web management interface, specifically in the goform/formdumpeasysetup endpoint. Attackers can exploit this flaw by sending a specially crafted request with a malicious curTime parameter, triggering a stack-based buffer overflow condition that can lead to denial of service.
Critical Impact
This network-accessible vulnerability in D-Link DIR-513 routers allows unauthenticated remote attackers to crash vulnerable devices through malformed HTTP requests to the web management interface, potentially disrupting network connectivity for all connected users.
Affected Products
- D-Link DIR-513 Firmware version 1.10
- D-Link DIR-513 Hardware (all revisions running vulnerable firmware)
Discovery Timeline
- 2026-03-09 - CVE-2025-70250 published to NVD
- 2026-03-11 - Last updated in NVD database
Technical Details for CVE-2025-70250
Vulnerability Analysis
This vulnerability is classified as CWE-121 (Stack-based Buffer Overflow), a memory corruption flaw that occurs when data written to a stack buffer exceeds the allocated space. In the D-Link DIR-513 firmware, the web server component fails to properly validate the length of the curTime parameter before copying it to a fixed-size stack buffer. The attack can be launched remotely over the network without authentication, requiring no user interaction. While the vulnerability primarily enables denial of service by crashing the device, stack buffer overflows can potentially be leveraged for more severe attacks depending on memory protections in place on the embedded system.
Root Cause
The root cause of this vulnerability lies in improper input validation within the goform/formdumpeasysetup handler. The firmware does not implement adequate bounds checking when processing the curTime parameter from incoming HTTP requests. When an attacker supplies a curTime value exceeding the expected buffer size, the overflow corrupts adjacent stack memory, leading to application crash or potentially allowing control flow hijacking on systems without stack protection mechanisms.
Attack Vector
The attack vector is network-based, targeting the D-Link DIR-513 router's web management interface. An attacker can exploit this vulnerability by:
- Crafting an HTTP request to the goform/formdumpeasysetup endpoint
- Including an oversized curTime parameter that exceeds buffer boundaries
- Sending the request to the router's management interface (typically on port 80)
- Triggering the stack buffer overflow, causing the device to crash or become unresponsive
The attack requires network access to the router's web interface but does not require any authentication credentials. This makes devices with internet-exposed management interfaces particularly vulnerable to remote exploitation.
Detection Methods for CVE-2025-70250
Indicators of Compromise
- Unexpected router reboots or service interruptions without administrative action
- HTTP requests containing abnormally long curTime parameters in router access logs
- Network traffic to goform/formdumpeasysetup from untrusted external sources
- Device unresponsiveness following web interface access attempts
Detection Strategies
- Monitor HTTP traffic to D-Link DIR-513 devices for requests to goform/formdumpeasysetup with unusually large parameter values
- Implement network intrusion detection signatures to flag potential buffer overflow attempts against D-Link web interfaces
- Review router logs for repeated crashes or unexpected restarts that may indicate exploitation attempts
- Deploy network segmentation to isolate IoT devices and monitor cross-segment traffic
Monitoring Recommendations
- Configure alerting for D-Link DIR-513 device availability and unexpected downtime
- Enable logging on network firewalls for traffic destined to router management interfaces
- Implement bandwidth monitoring to detect unusual traffic patterns targeting router endpoints
- Use SentinelOne Singularity for network visibility to identify exploitation attempts against IoT firmware vulnerabilities
How to Mitigate CVE-2025-70250
Immediate Actions Required
- Restrict access to the D-Link DIR-513 web management interface to trusted internal networks only
- Disable remote management if not required for operations
- Place D-Link DIR-513 devices behind a firewall with strict ingress filtering
- Monitor the D-Link Security Bulletin for firmware updates
Patch Information
As of the last NVD update on 2026-03-11, users should check the D-Link Security Bulletin for official patch availability. The D-Link Product Information page may also contain firmware update information. Given the DIR-513 model may be end-of-life, users should verify whether D-Link will release a security update or consider device replacement if no patch is forthcoming.
Workarounds
- Disable the web management interface entirely if remote administration is not required
- Configure firewall rules to block external access to the router's web interface on port 80
- Use VPN access for remote management instead of exposing the web interface directly
- Consider replacing the DIR-513 with a newer, actively supported router model if no patch is available
# Example firewall rule to restrict management interface access (iptables)
# Block external access to router management interface
iptables -A INPUT -p tcp --dport 80 -s ! 192.168.1.0/24 -j DROP
iptables -A INPUT -p tcp --dport 443 -s ! 192.168.1.0/24 -j DROP
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
