CVE-2026-91021

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{"affected": [{"affectedData": [{"product": "Trillium Notes", "vendor": "Trilium", "versions": [{"lessThanOrEqual": "v0.103.0", "status": "affected", "version": "0", "versionType": "custom"}]}], "source": "cret@cert.org"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Trilium Notes, version v0.103.0 and earlier, contains a stored cross-site scripting (XSS) vulnerability in the share renderer for webView notes due to improper HTML escaping of user-controlled #webViewSrc values. This vulnerability allows attackers with note-authoring privileges to inject arbitrary JavaScript that executes for any user who opens the shared note, including administrators."}], "id": "CVE-2026-91021", "lastModified": "2026-09-16T13:42:48.320", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.4, "baseSeverity": "MEDIUM", "confidentialityImpact": "LOW", "integrityImpact": "LOW", "privilegesRequired": "LOW", "scope": "CHANGED", "userInteraction": "REQUIRED", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N", "version": "3.1"}, "exploitabilityScore": 2.3, "impactScore": 2.7, "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-91021", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-09-14T19:41:10.009376Z", "version": "2.0.3"}}]}, "published": "2026-09-14T18:20:29.467", "references": [{"source": "cret@cert.org", "url": "https://vokecyber.com/research/trilium-share-renderer-stored-xss"}], "sourceIdentifier": "cret@cert.org", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-79"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{}

{"created": "2026-09-15T13:00:17.161523+00:00", "title": "Stored XSS in Trilium Notes Share Renderer Enables Cross\u2011Site Scripting for Note Authors", "updated": "2026-09-15T13:00:17.161531+00:00", "vendors": []}