# CVE-2025-34117

## Summary

- **CVE ID:** CVE-2025-34117
- **Severity:** CRITICAL
- **CVSS Score:** 9.3 (CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N)
- **CWE:** CWE-912, CWE-306, CWE-78
- **Published:** Jul 16, 2025
- **Last Modified:** Apr 7, 2026

## Description

A remote code execution vulnerability exists in multiple Netcore and Netis routers models with firmware released prior to August 2014 due to the presence of an undocumented backdoor listener on UDP port 53413. Exact version boundaries remain undocumented. An unauthenticated remote attacker can send specially crafted UDP packets to execute arbitrary commands on the affected device. This backdoor uses a hardcoded authentication mechanism and accepts shell commands post-authentication. Some device models include a non-standard implementation of the `echo` command, which may affect exploitability.

## Affected Products

- Netcore Technology — Router firmware (Prior to August 2014)
- Netis — Router firmware (Prior to August 2014)

## References

- [CNA](https://web.archive.org/web/20140828114943/http://blog.trendmicro.com/trendlabs-security-intelligence/netis-routers-leave-wide-open-backdoor/)
- [CNA](https://www.seebug.org/vuldb/ssvid-90227)
- [CNA](https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/exploits/linux/misc/netcore_udp_53413_backdoor.rb)
- [CNA](https://www.shadowserver.org/what-we-do/network-reporting/netcore-netis-router-vulnerability-scan-report/)
- [CNA](https://vulners.com/metasploit/MSF:EXPLOIT-LINUX-MISC-NETCORE_UDP_53413_BACKDOOR-)
- [CNA](https://www.vulncheck.com/advisories/netcore-netis-routers-backdoor-rce)
- [CNA](https://www.exploit-db.com/exploits/43387)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 27.85%
- **EPSS Percentile:** 98.0

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-11._