CVE-2026-71924 in VigorSwitch
Summary
by MITRE • 08/24/2026
Multiple DrayTek VigorSwitch models contain a command injection vulnerability in the getVid function. The vulnerability is caused by insufficient filtering of the username and password fields before command execution. A remote attacker can trigger this vulnerability via crafted input to execute arbitrary commands with root privileges. Exploitation requires valid administrative credentials for the device's web management interface.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 08/24/2026
The identified security flaw resides within the getVid function of multiple DrayTek VigorSwitch models, representing a critical command injection vulnerability that stems from insufficient sanitization of user-supplied input fields. Specifically, the username and password parameters are not adequately filtered or validated before being passed to underlying system commands for execution. This architectural oversight allows an attacker who has obtained valid administrative credentials through social engineering, credential stuffing, or other means to inject malicious shell metacharacters into these authentication fields. When the device processes this crafted input, it interprets the injected sequences as part of the command line rather than literal string data, thereby bypassing intended security controls and enabling arbitrary code execution with root privileges on the managed switch hardware.
From a technical perspective, this vulnerability aligns closely with CWE-78 Improper Neutralization of Special Elements used in an OS Command commonly known as OS Command Injection. The core issue is the failure to escape or encode special characters such as semicolons, ampersands, or pipe symbols within the input stream before it reaches the operating system's command interpreter. Because the vulnerability requires valid administrative credentials for exploitation, it does not constitute a remote code execution flaw accessible to unauthenticated actors but rather represents an elevated privilege abuse scenario. This distinction is crucial for risk assessment, as it limits the initial attack vector to individuals who have already breached or compromised the management interface authentication mechanism. However, once authenticated access is achieved, the impact is severe due to the root-level privileges granted by the underlying operating system of the network device.
The operational impact of this vulnerability extends beyond simple command execution on a single switch. In enterprise environments where VigorSwitches are deployed as part of a larger network infrastructure, an attacker gaining root access can manipulate routing tables, disable security features such as port security or ACLs, exfiltrate sensitive configuration data including SNMP community strings and SSH keys, or pivot to other internal systems by using the compromised switch as a foothold. This significantly expands the attack surface for lateral movement within the network. Furthermore, because these devices often handle critical traffic flows, compromising them can lead to service disruption through denial of service attacks or facilitate man-in-the-middle activities if SSL stripping capabilities are leveraged against connected endpoints.
Mitigation strategies must prioritize both immediate remediation and long-term hardening practices. The most effective solution is to apply the vendor-provided firmware updates that patch the getVid function by implementing proper input validation and command parameterization techniques. Until patches can be deployed, administrators should enforce strict access controls on the web management interface, restricting it to trusted IP addresses via firewall rules or VLAN segmentation. Additionally, enforcing multi-factor authentication for administrative accounts adds a critical layer of defense against credential theft, which is the prerequisite for exploiting this vulnerability. Regular auditing of login attempts and monitoring for anomalous command execution patterns can also aid in early detection of exploitation attempts.
In terms of threat intelligence frameworks, this vulnerability maps to MITRE ATT&CK techniques related to Command and Scripting Interpreter abuse, specifically T1059 which covers various scripting languages used by adversaries to execute commands on compromised systems. The requirement for valid credentials places the initial access phase under T1078 Valid Accounts, highlighting that while the technical flaw is severe, its exploitation relies heavily on prior authentication success. Security teams should treat this as a high-severity issue requiring immediate patching of all affected VigorSwitch models to prevent potential compromise of network infrastructure integrity and confidentiality.