CVE-2026-6986

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This issue affects the function mg_aes_gcm_decrypt of the file /src/tls_aes128.c of the component GCM Authentication Tag Handler. Such manipulation leads to improper verification of cryptographic signature. The attack may be performed from remote. A high complexity level is associated with this attack. The exploitability is assessed as difficult. The exploit has been disclosed publicly and may be used. Upgrading to version 7.21 is capable of addressing this issue. It is advisable to upgrade the affected component. VulDB has contacted the vendor early and they confirmed quickly, that this issue got fixed already."}, {"lang": "es", "value": "Una vulnerabilidad de seguridad ha sido detectada en Cesanta Mongoose hasta la versi\u00f3n 7.20. Este problema afecta a la funci\u00f3n mg_aes_gcm_decrypt del archivo /src/tls_aes128.c del componente Gestor de Etiquetas de Autenticaci\u00f3n GCM. Dicha manipulaci\u00f3n conduce a una verificaci\u00f3n incorrecta de la firma criptogr\u00e1fica. El ataque puede ser realizado de forma remota. Un alto nivel de complejidad est\u00e1 asociado con este ataque. La explotabilidad se eval\u00faa como dif\u00edcil. El exploit ha sido divulgado p\u00fablicamente y puede ser utilizado. La actualizaci\u00f3n a la versi\u00f3n 7.21 es capaz de solucionar este problema. Es aconsejable actualizar el componente afectado. VulDB contact\u00f3 al proveedor con antelaci\u00f3n y ellos confirmaron r\u00e1pidamente que este problema ya fue solucionado."}], "id": "CVE-2026-6986", "lastModified": "2026-10-26T21:10:00.170", "metrics": {"cvssMetricV2": [{"acInsufInfo": false, "baseSeverity": "LOW", "cvssData": {"accessComplexity": "HIGH", "accessVector": "NETWORK", "authentication": "NONE", "availabilityImpact": "NONE", "baseScore": 2.6, "confidentialityImpact": "NONE", "integrityImpact": "PARTIAL", "vectorString": "AV:N/AC:H/Au:N/C:N/I:P/A:N", "version": "2.0"}, "exploitabilityScore": 4.9, "impactScore": 2.9, "obtainAllPrivilege": false, "obtainOtherPrivilege": false, "obtainUserPrivilege": false, "source": "cna@vuldb.com", "type": "Secondary", "userInteractionRequired": false}], "cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 3.7, "baseSeverity": "LOW", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 2.2, "impactScore": 1.4, "source": "cna@vuldb.com", "type": "Secondary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "HIGH", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 2.9, "baseSeverity": "LOW", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "PROOF_OF_CONCEPT", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "NONE", "valueDensity": "NOT_DEFINED", "vectorString": "CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "version": "4.0", "vulnAvailabilityImpact": "NONE", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "LOW", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "cna@vuldb.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-6986", "options": [{"exploitation": "poc"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-04-27T13:33:26.520467Z", "version": "2.0.3"}}]}, "published": "2026-04-25T17:16:33.700", "references": [{"source": "cna@vuldb.com", "tags": ["Release Notes"], "url": "https://github.com/cesanta/mongoose/releases/tag/7.21"}, {"source": "cna@vuldb.com", "tags": ["Exploit", "Third Party Advisory"], "url": "https://github.com/dwBruijn/CVEs/blob/main/Mongoose/AESGCM.md"}, {"source": "cna@vuldb.com", "tags": ["Third Party Advisory", "VDB Entry"], "url": "https://vuldb.com/submit/796231"}, {"source": "cna@vuldb.com", "tags": ["Third Party Advisory", "VDB Entry"], "url": "https://vuldb.com/vuln/359529"}, {"source": "cna@vuldb.com", "tags": ["Permissions Required", "VDB Entry"], "url": "https://vuldb.com/vuln/359529/cti"}], "sourceIdentifier": "cna@vuldb.com", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-345"}, {"lang": "en", "value": "CWE-347"}], "source": "cna@vuldb.com", "type": "Secondary"}]}

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