# CVE-2025-34117 — Netcore Technology Router firmware

> As of 2026-04-07, CVE-2025-34117 is a Critical-severity (band derived from the CVSS v4.0 score, not stated by the CNA) vulnerability in Netcore Technology Router firmware, CVSS v4.0 9.3, EPSS 27.9% (98.0th percentile). Threadlinqs Intelligence links 1 tracked threat campaign to CVE-2025-34117, most recently “TuxBot v3 Evolution: LLM-Assisted IoT Botnet Framework With a Broken Multi-CVE Exploit Chain”.

**Last updated:** 2026-04-07

## What is CVE-2025-34117?

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.

The record classifies CVE-2025-34117 under weakness classes [CWE-912](https://cwe.mitre.org/data/definitions/912.html), [CWE-306](https://intel.threadlinqs.com/cwe/CWE-306), [CWE-78](https://intel.threadlinqs.com/cwe/CWE-78). 2 affected-product entries are recorded, across 2 vendors, listed below. The identifier was first published 469 days ago.

## Severity and exploitation probability

- **CVSS v4.0 base score:** 9.3 — Critical (derived from score) (`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`)
- **EPSS (FIRST):** 27.9% probability of exploitation in the next 30 days, higher than 98.0% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 10/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2025-07-16, last modified 2026-04-07

## Is CVE-2025-34117 being exploited?

Weaponised exploit code for CVE-2025-34117 is publicly available. 1 public proof-of-concept repository is tracked for this identifier. It currently carries a trending score of 38 in the Threadlinqs vulnerability feed.

- [trickest/cve](https://github.com/trickest/cve/blob/main/2025/CVE-2025-34117.md) (trickest)

## Affected products and versions

- **Netcore Technology**: Router firmware
- **Netis**: Router firmware

## How to fix CVE-2025-34117

No vendor patch reference has been recorded for CVE-2025-34117 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2025-34117

1 tracked threat in the Threadlinqs corpus references CVE-2025-34117, either in the campaign’s CVE list or as an indicator on the campaign record.

- [TuxBot v3 Evolution: LLM-Assisted IoT Botnet Framework With a Broken Multi-CVE Exploit Chain](https://intel.threadlinqs.com/threat/TL-2026-1366) — HIGH · 2026-07-15

## Sources

Enriched from CVE.org, NVD, FIRST EPSS, GitHub Security Advisories, public proof-of-concept repositories. Last verified by Threadlinqs on 2026-10-10. This product uses the NVD API but is not endorsed or certified by the NVD.

**Exploit and proof of concept**

- [raw.githubusercontent.com — exploit](https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/exploits/linux/misc/netcore_udp_53413_backdoor.rb)
- [vulners.com — third party advisory](https://vulners.com/metasploit/MSF:EXPLOIT-LINUX-MISC-NETCORE_UDP_53413_BACKDOOR-)
- [exploit-db.com — exploit](https://www.exploit-db.com/exploits/43387)

**Technical analysis**

- [web.archive.org — third party advisory](https://web.archive.org/web/20140828114943/http://blog.trendmicro.com/trendlabs-security-intelligence/netis-routers-leave-wide-open-backdoor/)
- [seebug.org — third party advisory](https://www.seebug.org/vuldb/ssvid-90227)

**Third-party advisory**

- [shadowserver.org — third party advisory](https://www.shadowserver.org/what-we-do/network-reporting/netcore-netis-router-vulnerability-scan-report/)
- [vulncheck.com — third party advisory](https://www.vulncheck.com/advisories/netcore-netis-routers-backdoor-rce)

Canonical: https://intel.threadlinqs.com/cve/CVE-2025-34117
Full detection coverage and IOCs for threats exploiting CVE-2025-34117 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp