CVE-2026-16771 CVE-2026-16771
Unauthenticated attackers on the LAN can access management endpoints to read configuration data and modify device settings due to missing server-side authentication.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-16771?
CVE-2026-16771 is a high-severity missing authorization vulnerability in AT&T Arris BGW210‑700, published on 28 Jul 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In firmware versions 2.7.7 and earlier, the Arris BGW210‑700 gateway fails to enforce any server‑side authentication on its /cgi-bin/*.ha management endpoints, relying solely on client‑side CSS/JavaScript gating that can be bypassed by any HTTP client. This allows unauthenticated attackers on the LAN to read sensitive configuration data, modify persistent device settings, or trigger backend diagnostic operations. The issue appears systemic across the CGI handler chain.
Weakness: CWE-306
Which versions are affected by CVE-2026-16771?
How do I fix CVE-2026-16771?
No fix has been published for CVE-2026-16771 yet. Limit exposure of the affected software until one is available.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-16771 being exploited?
There is no known exploitation of CVE-2026-16771 in the wild and no public exploit code.
Sources
Also known as GHSA-8rcq-gm95-4hqg.