CVE-2021-27245

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 v3 8.1 HIGH
CVSS v2.0 9.3 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

9.3^/10

CVSS v2.0 : HIGH

Vector : AV:N/AC:M/Au:N/C:C/I:C/A:C

Exploitability : 8.6 / Impact : 10.0

Access Vector NETWORK

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

References

Link	Resource
https://www.zerodayinitiative.com/advisories/ZDI-21-214/	Third Party Advisory VDB Entry
https://www.zerodayinitiative.com/advisories/ZDI-21-214/	Third Party Advisory VDB Entry

Configurations

Configuration 1 (hide)

AND

cpe:2.3:o:tp-link:archer_a7_firmware:*:*:*:*:*:*:*:*

cpe:2.3:h:tp-link:archer_a7:-:*:*:*:*:*:*:*

Configuration 2 (hide)

AND

cpe:2.3:o:tp-link:archer_a7_firmware:*:*:*:*:*:*:*:*

cpe:2.3:h:tp-link:archer_a7:-:*:*:*:*:*:*:*

History

21 Nov 2024, 05:57

Type	Values Removed	Values Added
References	~~() https://www.zerodayinitiative.com/advisories/ZDI-21-214/ - Third Party Advisory, VDB Entry~~	() https://www.zerodayinitiative.com/advisories/ZDI-21-214/ - Third Party Advisory, VDB Entry

Information

Published : 2021-03-29 21:15

Updated : 2024-11-21 05:57

NVD link : CVE-2021-27245

Mitre link : CVE-2021-27245

CVE.ORG link : CVE-2021-27245

JSON object : View

Products Affected

tp-link

archer_a7_firmware
archer_a7

CWE

CWE-693

Protection Mechanism Failure

{"id": "CVE-2021-27245", "metrics": {"cvssMetricV2": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"version": "2.0", "baseScore": 9.3, "accessVector": "NETWORK", "vectorString": "AV:N/AC:M/Au:N/C:C/I:C/A:C", "authentication": "NONE", "integrityImpact": "COMPLETE", "accessComplexity": "MEDIUM", "availabilityImpact": "COMPLETE", "confidentialityImpact": "COMPLETE"}, "acInsufInfo": false, "impactScore": 10.0, "baseSeverity": "HIGH", "obtainAllPrivilege": false, "exploitabilityScore": 8.6, "obtainUserPrivilege": false, "obtainOtherPrivilege": false, "userInteractionRequired": false}], "cvssMetricV30": [{"type": "Secondary", "source": "zdi-disclosures@trendmicro.com", "cvssData": {"scope": "UNCHANGED", "version": "3.0", "baseScore": 8.1, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 2.2}], "cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 8.1, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "HIGH", "privilegesRequired": "NONE", "confidentialityImpact": "HIGH"}, "impactScore": 5.9, "exploitabilityScore": 2.2}]}, "published": "2021-03-29T21:15:12.953", "references": [{"url": "https://www.zerodayinitiative.com/advisories/ZDI-21-214/", "tags": ["Third Party Advisory", "VDB Entry"], "source": "zdi-disclosures@trendmicro.com"}, {"url": "https://www.zerodayinitiative.com/advisories/ZDI-21-214/", "tags": ["Third Party Advisory", "VDB Entry"], "source": "af854a3a-2127-422b-91ae-364da2661108"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Secondary", "source": "zdi-disclosures@trendmicro.com", "description": [{"lang": "en", "value": "CWE-693"}]}], "descriptions": [{"lang": "en", "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."}, {"lang": "es", "value": "Esta vulnerabilidad permite una omisi\u00f3n 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 autenticaci\u00f3n para explotar esta vulnerabilidad. El fallo espec\u00edfico 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 c\u00f3digo en el contexto de root. Era ZDI-CAN-12309"}], "lastModified": "2024-11-21T05:57:40.570", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:tp-link:archer_a7_firmware:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "63702440-447F-40AF-84B9-CAE8DF07F990", "versionEndExcluding": "c7\\(us\\)_v5_210125"}], "operator": "OR"}, {"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:h:tp-link:archer_a7:-:*:*:*:*:*:*:*", "vulnerable": false, "matchCriteriaId": "8436480B-77AE-4910-AD80-2AC21F36992A"}], "operator": "OR"}], "operator": "AND"}, {"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:tp-link:archer_a7_firmware:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "F767618F-6E2D-4BCC-BAAD-5DC3EF8BC4B0", "versionEndExcluding": "a7\\(us\\)_v5_200220"}], "operator": "OR"}, {"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:h:tp-link:archer_a7:-:*:*:*:*:*:*:*", "vulnerable": false, "matchCriteriaId": "8436480B-77AE-4910-AD80-2AC21F36992A"}], "operator": "OR"}], "operator": "AND"}], "sourceIdentifier": "zdi-disclosures@trendmicro.com"}