Ameeba Security Research

Defensive CVE and exploit intelligence

Ameeba Blog Search
TRENDING · 1 WEEK
Attack Vector
Vendor
Severity

CVE-2025-30256: Denial of Service Vulnerability in Tenda AC6’s HTTP Header Parsing Functionality

Views: 431

Overview

The cybersecurity world is continuously evolving, and with it comes an alarming rise in vulnerabilities. One such vulnerability that has come to light recently is CVE-2025-30256. This vulnerability resides in the HTTP Header Parsing functionality of the Tenda AC6 V5.0 V02.03.01.110, a widely used router. The flaw can be exploited to cause a Denial of Service (DoS) condition, potentially leading to system compromise or data leakage. The severity of this vulnerability and its widespread impact necessitate immediate attention and proactive mitigation.

Vulnerability Summary

CVE ID: CVE-2025-30256
Severity: High (CVSS: 8.6)
Attack Vector: Network
Privileges Required: None
User Interaction: None
Impact: Denial of Service, Potential System Compromise, and Data Leakage

Affected Products

Ameeba Chat Icon Share secrets securely

Ameeba is private infrastructure for communication and sensitive work built on encrypted identity instead of exposed corporate identity systems.

Passwords, credentials, confidential files, screenshots, internal discussions, sensitive AI context, and private coordination should not become exposed across ordinary communication platforms.

  • • Encrypted identity
  • • Private Spaces for organizations and teams
  • • End-to-end encrypted chat, calls, files, and notes
  • • Sensitive AI work and protected collaboration
  • • Built for information that cannot leak

Our mission is to secure human work alongside AI.

Product | Affected Versions

Tenda AC6 | V5.0 V02.03.01.110

How the Exploit Works

The exploit works by having an attacker send a specially crafted series of HTTP requests to the vulnerable system. These malformed requests trigger a fault in the HTTP Header Parsing functionality of the Tenda AC6 router. The system is unable to handle these malformed requests, leading to a reboot of the system. This reboot can disrupt services and opens an opportunity for further exploitation, potentially leading to system compromise or data leakage.

Conceptual Example Code

Here is a conceptual example of such a malformed HTTP request that could exploit this vulnerability:

GET / HTTP/1.1
Host: target.example.com
Accept-Encoding: gzip, deflate
Accept: */*
Accept-Language: en
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64)
Connection: keep-alive
Content-Length: 99999999999

In this example, the “Content-Length” header is set to an excessively high value. The system attempts to allocate memory for the incoming data based on the “Content-Length” value. However, the excessive value leads to memory exhaustion, causing the system to reboot.

Mitigation Guidance

To mitigate this vulnerability, users are advised to apply the vendor-provided patch as soon as possible. If a patch is not yet available or cannot be applied immediately, users can use a Web Application Firewall (WAF) or Intrusion Detection System (IDS) to block or alert on suspicious network traffic patterns associated with this vulnerability. These systems can serve as a temporary mitigation measure until the patch can be applied.
Remember, staying updated with patches and employing robust security measures is the first line of defense against such vulnerabilities.

Want to discuss this further? Join the Ameeba Cybersecurity Group Chat.

Disclaimer:

The information and code presented in this article are provided for educational and defensive cybersecurity purposes only. Any conceptual or pseudocode examples are simplified representations intended to raise awareness and promote secure development and system configuration practices.

Do not use this information to attempt unauthorized access or exploit vulnerabilities on systems that you do not own or have explicit permission to test.

Ameeba and its authors do not endorse or condone malicious behavior and are not responsible for misuse of the content. Always follow ethical hacking guidelines, responsible disclosure practices, and local laws.

More posts

Ameeba Chat