FKIE_CVE-2026-75501

Vulnerability from fkie_nvd - Published: 2026-08-21 15:16 - Updated: 2026-08-21 16:18
Severity
Summary
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.
References
cret@cert.orghttps://drkq.github.io/security-research/calix-vu756733/
cret@cert.orghttps://kb.cert.org/vuls/id/756733
af854a3a-2127-422b-91ae-364da2661108https://www.kb.cert.org/vuls/id/756733
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "GS7 XGS (GS5239XG)",
          "vendor": "Calix",
          "versions": [
            {
              "lessThanOrEqual": "Firmware EXOS/6.6.47",
              "status": "affected",
              "version": "0",
              "versionType": "custom"
            }
          ]
        }
      ],
      "source": "cret@cert.org"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "A vulnerability in the Calix EXOS firmware for the GS7 XGS (GS5239XG) residential router allows unauthenticated remote attackers to modify NAT port\u2011forwarding 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."
    }
  ],
  "id": "CVE-2026-75501",
  "lastModified": "2026-08-21T16:18:17.470",
  "metrics": {},
  "published": "2026-08-21T15:16:47.070",
  "references": [
    {
      "source": "cret@cert.org",
      "url": "https://drkq.github.io/security-research/calix-vu756733/"
    },
    {
      "source": "cret@cert.org",
      "url": "https://kb.cert.org/vuls/id/756733"
    },
    {
      "source": "af854a3a-2127-422b-91ae-364da2661108",
      "url": "https://www.kb.cert.org/vuls/id/756733"
    }
  ],
  "sourceIdentifier": "cret@cert.org",
  "vulnStatus": "Received"
}



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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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