# CVE-2025-50659: D-Link DI-8003 buffer overflow in /user.asp

Source: https://junglewise.ai/threats/cve-2025-50659-d-link-di-8003-buffer-overflow-in-user-asp  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-04-08. Updated: 2026-07-25  
License: CC BY 4.0 with a link back

CVE-2025-50659 · Severity: high · CVSS 7.5 · Published 2026-04-08

A security vulnerability exists in the D-Link DI-8003 enterprise router that could allow an attacker to crash the device. This router is used to manage network traffic and provide internet access for business environments. An exploit could lead to a total loss of network availability, disrupting operations and requiring a manual restart or replacement of the hardware.

Technologies: [Dlink Di-8003](https://junglewise.ai/threats/technologies/di-8003), [Dlink Di-8003 Firmware](https://junglewise.ai/threats/technologies/di-8003-firmware). Vendors: [Dlink](https://junglewise.ai/threats/vendors/dlink).

## Quick answers

**Is CVE-2025-50659 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2025-50659 being exploited in the wild.

**How severe is CVE-2025-50659?** High severity, with a CVSS score of 7.5, published 8 April 2026.

**Which products and versions are affected?** D-Link DI-8003 16.07.26A1.

**Is there a fix for CVE-2025-50659?** No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

**How is CVE-2025-50659 attacked?** It is attacked over the network.

**Am I affected by CVE-2025-50659?** Check whether you run Dlink Di-8003 or Dlink Di-8003 Firmware. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A stack-based buffer overflow (CWE-121) exists in the D-Link DI-8003 router, specifically within the /user.asp endpoint. The vulnerability is caused by improper handling and insufficient bounds checking of the 'custom_error' parameter. A remote, unauthenticated attacker can exploit this by sending a specially crafted HTTP request to the affected endpoint. Successful exploitation results in a crash of the web service or the device itself, leading to a denial-of-service (DoS) state. The manufacturer has indicated this product is End-of-Life (EoL), and no official patch is expected.

## Affected products

- D-Link DI-8003 16.07.26A1

## Timeline

- 2026-04-08: advisory: Initial disclosure of CVE-2025-50659
- 2026-04-15: other: Vendor confirmed product is End-of-Life (EoL) and will not receive updates.

## References

- [https://github.com/xiaotea/iot-vulnerability-collection/blob/main/README.md](https://github.com/xiaotea/iot-vulnerability-collection/blob/main/README.md)
- [https://supportannouncement.us.dlink.com/security/publication.aspx?name=SAP10505](https://supportannouncement.us.dlink.com/security/publication.aspx?name=SAP10505)
- [https://www.dlink.com/en/security-bulletin/](https://www.dlink.com/en/security-bulletin/)

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- [D-Link DI-8003 buffer overflow in wan_ping.asp](https://junglewise.ai/threats/cve-2025-50669-d-link-di-8003-buffer-overflow-in-wan-ping-asp)