CVE-2026-42451

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{"affected": [{"affectedData": [{"product": "grimmory", "vendor": "grimmory-tools", "versions": [{"status": "affected", "version": "< 2.3.1"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Grimmory is a self-hosted digital library. Prior to version 2.3.1, a stored cross-site scripting (XSS) vulnerability in Grimmory's browser-based EPUB reader allows an attacker to embed arbitrary JavaScript in a crafted EPUB file. When a victim opens the book, the script executes in their browser with full access to the Grimmory application's session context. This can enable session token theft and account takeover, including administrative access if an administrator opens the affected book. This issue has been patched in version 2.3.1."}, {"lang": "es", "value": "Grimmory es una biblioteca digital autoalojada. Antes de la versi\u00f3n 2.3.1, una vulnerabilidad de cross-site scripting (XSS) almacenado en el lector de EPUB basado en navegador de Grimmory permite a un atacante incrustar JavaScript arbitrario en un archivo EPUB manipulado. Cuando una v\u00edctima abre el libro, el script se ejecuta en su navegador con acceso completo al contexto de sesi\u00f3n de la aplicaci\u00f3n Grimmory. Esto puede permitir el robo de tokens de sesi\u00f3n y la toma de control de cuentas, incluyendo acceso administrativo si un administrador abre el libro afectado. Este problema ha sido parcheado en la versi\u00f3n 2.3.1."}], "id": "CVE-2026-42451", "lastModified": "2026-07-24T21:10:00.143", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "LOCAL", "availabilityImpact": "LOW", "baseScore": 6.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:H/I:H/A:L", "version": "3.1"}, "exploitabilityScore": 0.8, "impactScore": 5.5, "source": "security-advisories@github.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-42451", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-05-12T13:16:55.827303Z", "version": "2.0.3"}}]}, "published": "2026-05-08T23:16:38.680", "references": [{"source": "security-advisories@github.com", "url": "http://github.com/grimmory-tools/grimmory/releases/tag/v2.3.1"}, {"source": "security-advisories@github.com", "url": "https://github.com/grimmory-tools/grimmory/security/advisories/GHSA-frv6-5wq5-9p24"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-79"}, {"lang": "en", "value": "CWE-80"}], "source": "security-advisories@github.com", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,2.3.1)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "cna", "scores": [{"score": 100.0, "source": "cna"}]}, "original": {"product": "grimmory", "source": "cna", "vendor": "grimmory-tools"}, "product": "grimmory", "vendor": "grimmory-tools"}], "created": "2026-05-09T00:30:21.261607+00:00", "updated": "2026-05-10T21:24:40.784368+00:00", "vendors": ["grimmory-tools", "grimmory-tools$PRODUCT$grimmory"]}