CVE-2026-55839

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{"affected": [{"affectedData": [{"product": "kestra", "vendor": "kestra-io", "versions": [{"status": "affected", "version": "< 1.3.24"}]}], "source": "security-advisories@github.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Kestra is an open-source, event-driven orchestration platform. Prior to 1.3.24, Kestra's custom Markdown parser in ui/src/utils/markdown_plugins/link.ts allows a user with permission to create or update a Flow description to inject JavaScript event-handler attributes through the custom [[link]] syntax, causing stored cross-site scripting when another user opens the description or information panel in the Flow list. This issue is fixed in version 1.3.24."}, {"lang": "es", "value": "Kestra es una plataforma de orquestaci\u00f3n de c\u00f3digo abierto y basada en eventos. Antes de la versi\u00f3n 1.3.24, el analizador de Markdown personalizado de Kestra en ui/src/utils/markdown_plugins/link.ts permite a un usuario con permiso para crear o actualizar la descripci\u00f3n de un Flow inyectar atributos de gestor de eventos de JavaScript a trav\u00e9s de la sintaxis personalizada [[link]], causando cross-site scripting almacenado cuando otro usuario abre la descripci\u00f3n o el panel de informaci\u00f3n en la lista de Flows. Este problema se ha solucionado en la versi\u00f3n 1.3.24."}], "id": "CVE-2026-55839", "lastModified": "2026-10-22T22:10:00.250", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 8.7, "baseSeverity": "HIGH", "confidentialityImpact": "HIGH", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "CHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:N", "version": "3.1"}, "exploitabilityScore": 2.3, "impactScore": 5.8, "source": "security-advisories@github.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-55839", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-08-18T17:28:28.962947Z", "version": "2.0.3"}}]}, "published": "2026-08-18T16:17:53.710", "references": [{"source": "security-advisories@github.com", "url": "https://github.com/kestra-io/kestra/commit/6c8e6d099ed172cbb6b003b7fb30b7bb1f8f710e"}, {"source": "security-advisories@github.com", "url": "https://github.com/kestra-io/kestra/pull/16835"}, {"source": "security-advisories@github.com", "url": "https://github.com/kestra-io/kestra/releases/tag/v1.3.24"}, {"source": "security-advisories@github.com", "url": "https://github.com/kestra-io/kestra/security/advisories/GHSA-34pm-923j-7wf8"}], "sourceIdentifier": "security-advisories@github.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-79"}], "source": "security-advisories@github.com", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,1.3.24)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "kestra", "source": "cna", "vendor": "kestra-io"}, "product": "kestra", "vendor": "kestra-io"}], "created": "2026-08-18T16:30:05.990016+00:00", "updated": "2026-08-18T17:30:15.395106+00:00", "vendors": ["kestra-io", "kestra-io$PRODUCT$kestra"]}