A vulnerability in the Calix EXOS firmware for the GS7 XGS (GS5239XG) residential router allows unauthenticated remote attackers to modify NAT… (CVE-2026-75501)
A vulnerability in the Calix EXOS firmware for the GS7 XGS (GS5239XG) residential router allows unauthenticated remote attackers to modify NAT port‑forwarding rules via the UPnP WANIPConnection service. The device exposes the MiniUPnPd control endpoint on the WAN interface on TCP port 5000 without access controls. A remote attacker can send crafted SOAP requests to add, delete, or enumerate port mappings, or to query the external IP address, without authentication. Successful exploitation may enable bypass of the firewall/NAT boundary and exposure of internal LAN services to the public internet.
AI Analysis
Technical Summary
The Calix EXOS firmware for the GS7 XGS (GS5239XG) router has a vulnerability (CVE-2026-75501) where the MiniUPnPd control endpoint is exposed on the WAN interface on TCP port 5000 without access controls. This allows unauthenticated remote attackers to interact with the UPnP WANIPConnection service and modify NAT port-forwarding rules by sending crafted SOAP requests. The attacker can add, delete, or enumerate port mappings or query the external IP address, potentially bypassing firewall and NAT protections.
Potential Impact
Successful exploitation allows unauthenticated remote attackers to modify NAT port-forwarding rules, potentially exposing internal LAN services to the public internet by bypassing firewall and NAT boundaries. This can lead to unauthorized access to internal network resources.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or patch information is provided in the available data.
A vulnerability in the Calix EXOS firmware for the GS7 XGS (GS5239XG) residential router allows unauthenticated remote attackers to modify NAT… (CVE-2026-75501)
Description
A vulnerability in the Calix EXOS firmware for the GS7 XGS (GS5239XG) residential router allows unauthenticated remote attackers to modify NAT port‑forwarding rules via the UPnP WANIPConnection service. The device exposes the MiniUPnPd control endpoint on the WAN interface on TCP port 5000 without access controls. A remote attacker can send crafted SOAP requests to add, delete, or enumerate port mappings, or to query the external IP address, without authentication. Successful exploitation may enable bypass of the firewall/NAT boundary and exposure of internal LAN services to the public internet.
CVSS v3.1
Score 7.5high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The Calix EXOS firmware for the GS7 XGS (GS5239XG) router has a vulnerability (CVE-2026-75501) where the MiniUPnPd control endpoint is exposed on the WAN interface on TCP port 5000 without access controls. This allows unauthenticated remote attackers to interact with the UPnP WANIPConnection service and modify NAT port-forwarding rules by sending crafted SOAP requests. The attacker can add, delete, or enumerate port mappings or query the external IP address, potentially bypassing firewall and NAT protections.
Potential Impact
Successful exploitation allows unauthenticated remote attackers to modify NAT port-forwarding rules, potentially exposing internal LAN services to the public internet by bypassing firewall and NAT boundaries. This can lead to unauthorized access to internal network resources.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or patch information is provided in the available data.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-f7wj-3v6p-grpv
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-75501"]
- Database Specific Severity
- HIGH
- Cvss Version
- 3.1
Threat ID: 6aaa081e55bf5e2cf5ea54de
Added to database: 09/16/2026, 03:08:14 UTC
Last enriched: 09/16/2026, 03:16:39 UTC
Last updated: 09/16/2026, 03:28:49 UTC
Views: 3
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