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CVE-2021-27245

Estado: ModificadaAlta (8.1)—

This vulnerability allows a firewall bypass on affected installations of TP-Link Archer A7 prior to Archer C7(US)_V5_210125 and Archer A7(US)_V5_200220 AC1750 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of IPv6 connections. The issue results from the lack of proper filtering of IPv6 SSH connections. An attacker can leverage this in conjunction with other vulnerabilities to execute code in the context of root. Was ZDI-CAN-12309.

CVSS

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

Tecnologías afectadas (1)

Tp-link — Archer A7 Firmware

CWE

Referencias

JSON original (NVD)

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          "vectorString": "AV:N/AC:M/Au:N/C:C/I:C/A:C",
          "authentication": "NONE",
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  "published": "2021-03-29T21:15:12.953",
  "references": [
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      "url": "https://www.zerodayinitiative.com/advisories/ZDI-21-214/",
      "tags": [
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  "vulnStatus": "Modified",
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          "value": "CWE-693"
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      "value": "This vulnerability allows a firewall bypass on affected installations of TP-Link Archer A7 prior to Archer C7(US)_V5_210125 and Archer A7(US)_V5_200220 AC1750 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the handling of IPv6 connections. The issue results from the lack of proper filtering of IPv6 SSH connections. An attacker can leverage this in conjunction with other vulnerabilities to execute code in the context of root. Was ZDI-CAN-12309."
    },
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      "value": "Esta vulnerabilidad permite una omisión del firewall en las instalaciones afectadas de TP-Link Archer A7 antes de los enrutadores Archer C7(EE. UU.)_V5_210125 y Archer A7(EE. UU.)_V5_200220 AC1750. No es requerida una autenticación para explotar esta vulnerabilidad. El fallo específico se presenta dentro del manejo de las conexiones IPv6. El problema resulta de una falta de filtrado apropiado de las conexiones SSH IPv6. Un atacante puede aprovechar esto junto con otras vulnerabilidades para ejecutar código en el contexto de root. Era ZDI-CAN-12309"
    }
  ],
  "lastModified": "2026-06-17T03:44:32.293",
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