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TI-2026-13960 Aliases CVE-2026-16771GHSA-8rcq-gm95-4hqg

Missing authentication in AT&T Arris BGW210‑700

Priority MEDIUM 40CWE-306Published · Updated

Key facts

Attack vector
Adjacent network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-306.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00425 36th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
AT&TArris BGW210‑700up to 2.7.7—No fix listedCNA
  • Arris BGW210‑700 VendorAT&T Affected up to 2.7.7 Fixed in — No fix listed CNA

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-16771
  2. 2026-10-03 Alias added: GHSA-8rcq-gm95-4hqg

References

Other 1

  • TI-2001-00166 Buffer overflow in AT&T WinVNC (Virtual Network Computing) server 3.3.3r7 and earlier… CVSS 2.0HIGH 10.0
  • TI-2001-00165 Buffer overflow in AT&T WinVNC (Virtual Network Computing) client 3.3.3r7 and earlier… CVSS 2.0HIGH 7.6
  • TI-1999-01008 Vulnerability in rexec daemon (rexecd) in AT&T TCP/IP 4.0 for various SVR4 systems allows… CVSS 2.0HIGH 10.0
  • TI-2022-09848 A heap-based buffer overflow exists in XML Decompression DecodeTreeBlock in AT&T Labs… CVSS 3.1CRITICAL 9.8
  • TI-2021-04874 Heap-based buffer overflow in AT&T CVSS 3.1CRITICAL 9.8
  • TI-2021-04875 Heap-based buffer overflow in AT&T CVSS 3.1CRITICAL 9.8
See all 29 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences