CVE-2026-16771

High

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.

SeverityHigh
CVSS8.8
Exploit probability—
ProductArris BGW210‑700
PublishedJul 28, 2026
First seenJul 28, 2026

How to fix

Sources list no fixed version or patch link for this vulnerability.

Affected products

ProductAffected versionsFixed in
AT&T Arris BGW210‑700v ≤ 2.7.7—

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