DrayTek VigorSwitch Edit ACE acl_general_setup Edit ACE Name buffer overflow

Summaryinfo

A vulnerability was found in DrayTek VigorSwitch. It has been rated as very critical. Affected by this vulnerability is the function acl_general_setup Edit ACE of the component Edit ACE. Performing a manipulation of the argument Name results in buffer overflow. This vulnerability is cataloged as CVE-2026-71940. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability, which was classified as very critical, was found in DrayTek VigorSwitch (version unknown). This affects the function acl_general_setup Edit ACE of the component Edit ACE. The manipulation of the argument name with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Multiple DrayTek VigorSwitch models contain a buffer overflow vulnerability in the acl_general_setup Edit ACE function. The vulnerability is caused by copying the name field into a fixed-size buffer without length validation. A remote attacker can trigger this vulnerability via crafted input, causing a denial of service or potentially executing arbitrary commands. Exploitation requires valid administrative credentials for the device's web management interface.

It is possible to read the advisory at draytek.com. This vulnerability is uniquely identified as CVE-2026-71940 since 08/08/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. Additional levels of successful authentication are needed for exploitation. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 08/24/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Type

• Router Operating System

Vendor

• DrayTek

Name

• VigorSwitch

License

• commercial

CPE 2.3info

• 🔒

CPE 2.2info

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