CVE-2026-6985

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{"affected": [{"affectedData": [{"cpes": ["cpe:2.3:a:cesanta:mongoose:*:*:*:*:*:*:*:*"], "modules": ["TCP Option Handler"], "product": "Mongoose", "vendor": "Cesanta", "versions": [{"status": "affected", "version": "7.0"}, {"status": "affected", "version": "7.1"}, {"status": "affected", "version": "7.2"}, {"status": "affected", "version": "7.3"}, {"status": "affected", "version": "7.4"}, {"status": "affected", "version": "7.5"}, {"status": "affected", "version": "7.6"}, {"status": "affected", "version": "7.7"}, {"status": "affected", "version": "7.8"}, {"status": "affected", "version": "7.9"}, {"status": "affected", "version": "7.10"}, {"status": "affected", "version": "7.11"}, {"status": "affected", "version": "7.12"}, {"status": "affected", "version": "7.13"}, {"status": "affected", "version": "7.14"}, {"status": "affected", "version": "7.15"}, {"status": "affected", "version": "7.16"}, {"status": "affected", "version": "7.17"}, {"status": "affected", "version": "7.18"}, {"status": "affected", "version": "7.19"}, {"status": "affected", "version": "7.20"}, {"status": "unaffected", "version": "7.21"}]}], "source": "cna@vuldb.com"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:cesanta:mongoose:*:*:*:*:*:*:*:*", "matchCriteriaId": "CFB6060D-2132-492F-8C8D-CC053CCFBC80", "versionEndExcluding": "7.21", "versionStartIncluding": "7.0", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "A weakness has been identified in Cesanta Mongoose up to 7.20. This vulnerability affects the function handle_opt of the file /src/net_builtin.c of the component TCP Option Handler. This manipulation of the argument optlen causes infinite loop. The attack is possible to be carried out remotely. The exploit has been made available to the public and could be used for attacks. Upgrading to version 7.21 is able to resolve this issue. Upgrading the affected component is advised. VulDB has contacted the vendor early and they confirmed quickly, that this issue got fixed already."}, {"lang": "es", "value": "Se ha identificado una debilidad en Cesanta Mongoose hasta la versi\u00f3n 7.20. Esta vulnerabilidad afecta a la funci\u00f3n handle_opt del archivo /src/net_builtin.c del componente Gestor de Opciones TCP. Esta manipulaci\u00f3n del argumento optlen causa un bucle infinito. El ataque es posible de ser llevado a cabo de forma remota. El exploit ha sido puesto a disposici\u00f3n del p\u00fablico y podr\u00eda ser utilizado para ataques. La actualizaci\u00f3n a la versi\u00f3n 7.21 es capaz de resolver este problema. Se aconseja 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-2026-6985", "lastModified": "2026-10-26T22:10:00.163", "metrics": {"cvssMetricV2": [{"acInsufInfo": false, "baseSeverity": "MEDIUM", "cvssData": {"accessComplexity": "LOW", "accessVector": "NETWORK", "authentication": "NONE", "availabilityImpact": "PARTIAL", "baseScore": 5.0, "confidentialityImpact": "NONE", "integrityImpact": "NONE", "vectorString": "AV:N/AC:L/Au:N/C:N/I:N/A:P", "version": "2.0"}, "exploitabilityScore": 10.0, "impactScore": 2.9, "obtainAllPrivilege": false, "obtainOtherPrivilege": false, "obtainUserPrivilege": false, "source": "cna@vuldb.com", "type": "Secondary", "userInteractionRequired": false}], "cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "LOW", "baseScore": 5.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 1.4, "source": "cna@vuldb.com", "type": "Secondary"}, {"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 7.5, "baseSeverity": "HIGH", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 3.9, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 5.5, "baseSeverity": "MEDIUM", "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:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/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": "LOW", "vulnConfidentialityImpact": "NONE", "vulnIntegrityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "cna@vuldb.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-6985", "options": [{"exploitation": "poc"}, {"automatable": "yes"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-04-27T12:35:19.133011Z", "version": "2.0.3"}}]}, "published": "2026-04-25T17:16:33.520", "references": [{"source": "cna@vuldb.com", "tags": ["Product", "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/TCP_opt_dos.md"}, {"source": "cna@vuldb.com", "tags": ["Third Party Advisory", "VDB Entry"], "url": "https://vuldb.com/submit/796230"}, {"source": "cna@vuldb.com", "tags": ["Third Party Advisory", "VDB Entry"], "url": "https://vuldb.com/vuln/359528"}, {"source": "cna@vuldb.com", "tags": ["Permissions Required", "VDB Entry"], "url": "https://vuldb.com/vuln/359528/cti"}], "sourceIdentifier": "cna@vuldb.com", "vulnStatus": "Analyzed", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-404"}, {"lang": "en", "value": "CWE-835"}], "source": "cna@vuldb.com", "type": "Secondary"}]}

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