CVE-2026-71938 DrayTek VigorSwitch Multiple Models Buffer Overflow via switch_lan_gvrp
Remote attackers with admin credentials can trigger a buffer overflow in DrayTek switches, leading to denial of service or arbitrary code execution.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-71938?
CVE-2026-71938 is a high-severity memory corruption vulnerability in DrayTek Corporation VigorSwitch FX2120, published on 24 Aug 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
Multiple DrayTek VigorSwitch models contain a buffer overflow vulnerability in the switch_lan_gvrp function. The vulnerability is caused by unsafe copying of the portList field into an undersized buffer. 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.
Weakness: CWE-120
Which versions are affected by CVE-2026-71938?
How do I fix CVE-2026-71938?
No fix has been published for CVE-2026-71938 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2026-71938 being exploited?
There is no known exploitation of CVE-2026-71938 in the wild and no public exploit code.
Sources
Also known as GHSA-x775-m3v2-h228.