# CVE-2026-52191: UTT nv518G Buffer Overflow in gohead/sub_444C8C

Source: https://junglewise.ai/threats/cve-2026-52191-utt-nv518g-buffer-overflow-in-gohead-sub-444c8c  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-07-02. Updated: 2026-07-02  
License: CC BY 4.0 with a link back

CVE-2026-52191 · Severity: info · CVSS 9.8 · Published 2026-07-02

A security vulnerability exists in the UTT nv518G enterprise router. An attacker can send a specially crafted web request to the device to cause it to crash or potentially take full control of the system. This could lead to a total disruption of network services or unauthorized access to corporate data passing through the router.

Technologies: [UTT NV518G](https://junglewise.ai/threats/technologies/nv518g). Vendors: [UTT](https://junglewise.ai/threats/vendors/utt).

## Quick answers

**Is CVE-2026-52191 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-52191 being exploited in the wild.

**How severe is CVE-2026-52191?** Informational severity, with a CVSS score of 9.8, published 2 July 2026.

**Which products and versions are affected?** UTT NV518G nv518GV3v3.2.7-210919-161313.

**Is there a fix for CVE-2026-52191?** 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-2026-52191 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-52191?** Check whether you run UTT NV518G at an affected version. 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 exists in the UTT nv518G router (firmware version nv518GV3v3.2.7-210919-161313) within the GoAhead web server component. The vulnerability is located in function sub_444C8C, where the 'port' parameter from an HTTP POST request is retrieved via websGetVar(). This user-controlled string is then appended to a fixed-size 104-byte stack buffer using strcat() without any length validation. An attacker providing a 'port' value exceeding approximately 72 bytes can overwrite the saved return address on the stack, leading to a denial of service (DoS) or remote code execution (RCE). No authentication is required to exploit this vulnerability over the network.

## Affected products

- UTT nv518G nv518GV3v3.2.7-210919-161313

## Timeline

- 2026-07-02: disclosed: Initial disclosure via NVD and GitHub report

## References

- [https://github.com/akuma-QAQ/CVEreport/tree/main/518G/FUN_00444c8c](https://github.com/akuma-QAQ/CVEreport/tree/main/518G/FUN_00444c8c)
- [https://utt.com.cn/downloadcenter.php?filetypeid=3&model=518G&lang=zhcn](https://utt.com.cn/downloadcenter.php?filetypeid=3&model=518G&lang=zhcn)

## Related threats

- [UTT nv518G command injection in gohead/sub_445C5C](https://junglewise.ai/threats/cve-2026-52192-utt-nv518g-command-injection-in-gohead-sub-445c5c)
- [UTT nv518G buffer overflow in gohead/sub_487330](https://junglewise.ai/threats/cve-2026-52189-utt-nv518g-buffer-overflow-in-gohead-sub-487330)
- [UTT nv518G buffer overflow in gohead component](https://junglewise.ai/threats/cve-2026-52188-utt-nv518g-buffer-overflow-in-gohead-component)
- [UTT nv518G buffer overflow in GoAhead sub_483ba0](https://junglewise.ai/threats/cve-2026-52187-utt-nv518g-buffer-overflow-in-goahead-sub-483ba0)
- [UTT nv518G buffer overflow in gohead/sub_448384](https://junglewise.ai/threats/cve-2026-52190-utt-nv518g-buffer-overflow-in-gohead-sub-448384)