CVE-2026-41431

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{"affected": [{"affectedData": [{"product": "desktop", "vendor": "zen-browser", "versions": [{"status": "affected", "version": "< 1.19.9b"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Zen is a firefox-based browser. Prior to 1.19.9b, Zen Browser ships a Mozilla Application Resource (MAR) updater (org.mozilla.updater) that has had all MAR signature verification stripped from the Firefox codebase it was forked from. The MAR files served to users contain zero cryptographic signatures, and the updater binary contains zero cryptographic verification code. This eliminates the defense-in-depth that MAR signing provides. If the update server or GitHub release pipeline is compromised, arbitrary unsigned code can be delivered to all Zen users via the auto-update mechanism. This vulnerability is fixed in 1.19.9b."}, {"lang": "es", "value": "Zen es un navegador basado en Firefox. Antes de la 1.19.9b, Zen Browser incluye un actualizador de Recursos de Aplicaci\u00f3n de Mozilla (MAR) (org.mozilla.updater) al que se le hab\u00eda eliminado toda la verificaci\u00f3n de firma MAR del c\u00f3digo base de Firefox del que se bifurc\u00f3. Los archivos MAR servidos a los usuarios contienen cero firmas criptogr\u00e1ficas, y el binario del actualizador contiene cero c\u00f3digo de verificaci\u00f3n criptogr\u00e1fica. Esto elimina la defensa en profundidad que proporciona la firma MAR. Si el servidor de actualizaciones o el pipeline de lanzamiento de GitHub se ve comprometido, c\u00f3digo arbitrario sin firmar puede ser entregado a todos los usuarios de Zen a trav\u00e9s del mecanismo de autoactualizaci\u00f3n. Esta vulnerabilidad est\u00e1 corregida en la 1.19.9b."}], "id": "CVE-2026-41431", "lastModified": "2026-10-26T18:10:00.173", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "HIGH", "baseScore": 8.0, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "HIGH", "scope": "CHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.3, "impactScore": 6.0, "source": "security-advisories@github.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-41431", "options": [{"exploitation": "poc"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-05-11T18:31:13.968267Z", "version": "2.0.3"}}]}, "published": "2026-05-11T18:16:34.280", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/zen-browser/desktop/commit/270db6d6713d2c6c14d9df0b4bc7662843d3d54e"}, {"source": "security-advisories@github.com", "url": "https://github.com/zen-browser/desktop/security/advisories/GHSA-qpj9-m8jc-mw6q"}, {"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "url": "https://github.com/zen-browser/desktop/security/advisories/GHSA-qpj9-m8jc-mw6q"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-347"}], "source": "security-advisories@github.com", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "generic", "value": "[0,1.19.9b)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "cna", "scores": [{"score": 100.0, "source": "cna"}]}, "original": {"product": "desktop", "source": "cna", "vendor": "zen-browser"}, "product": "desktop", "vendor": "zen-browser"}], "created": "2026-05-11T19:15:42.838292+00:00", "updated": "2026-05-12T09:22:51.276770+00:00", "vendors": ["zen-browser", "zen-browser$PRODUCT$desktop"]}