Security researchers have identified several flaws in the ZTE F680 over recent years. While many are patched in newer firmware versions, older devices may still be at risk. CVE-2020-6868: Parameter Tampering & Input Validation
Because the router fails to check if the user has an active login session, the CGI script executes the command, enabling the Telnet daemon with hardcoded or default credentials.
Web pages responsible for network diagnostics (such as Ping or Traceroute utilities) directly pass user-supplied IP addresses or hostnames into system shell commands without adequate filtering.
: Check your ISP management portal or the ZTE Support Portal for the latest security patches. Many modern ISPs push these updates automatically; ensure this feature is enabled.
Attackers scanning port 80 (HTTP), port 443 (HTTPS), or port 23 (Telnet) can use these hardcoded credentials to gain full control of the device's web interface or command-line shell. Web Interface Command Injection zte f680 exploit
component, allowing unauthenticated attackers to execute arbitrary system commands. Mitigation and Best Practices For users and administrators of the official security bulletins recommend several defensive measures: CVE-2020-6868 - NVD
The attacker downloads the encrypted configuration file directly via an unauthenticated file path.
Before examining the exploits, we must understand the hardware's role. Unlike a standard retail router, the ZTE F680 is often provided by Internet Service Providers (ISPs) as a "managed device." This means the ISP has remote administrative access (TR-069 protocol) to change settings, push firmware updates, or troubleshoot line issues.
: An attacker can modify the gateway name by inserting malicious scripts. When a user views the device topology page, the script executes, potentially leading to session hijacking or sensitive data theft. Configuration Decryption Vulnerabilities : File : db_user_cfg.xml . Security researchers have identified several flaws in the
By appending specific patterns to the URL string (similar to the famous path traversal and authentication bypass techniques found in other GPON routers like CVE-2018-10561), an unauthenticated attacker can skip the login page and directly query internal configuration pages, such as create_backup.gch or get_set.gch . C. Command Injection via Web Forms
An attacker inputs malicious payloads containing shell metacharacters (such as ; , && , or || ) into the diagnostic input field. For example:
The used by Internet Service Providers (ISPs) globally to deliver fiber-to-the-home (FTTH) broadband. Because residential gateways handle all incoming and outgoing network traffic, they are prime targets for cybercriminals and security researchers alike. Analyzing security flaws associated with the "ZTE F680 exploit" ecosystem reveals critical architectural weaknesses in embedded firmware, varying from input validation failures to improper access control. Known Vulnerabilities in the ZTE F680
The first widely documented vulnerability affecting the ZTE F680 is CVE-2020-6868, which exists in . This flaw stems from improper access controls on certain web-based management interfaces. Web pages responsible for network diagnostics (such as
From there, an adversary can:
Compromised routers are routinely recruited into IoT botnets (like Mirai variants) to launch massive Distributed Denial of Service (DDoS) attacks.
Several documented security flaws affect different generations of the ZTE F680 firmware. These range from client-side script injections to severe backend validation design flaws. 1. HTTP Bypassing and Input Validation (CVE-2020-6868)