CVE-2026-87809

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-87809", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "state": "PUBLISHED", "assignerShortName": "VulnCheck", "dateReserved": "2026-09-09T10:30:15.669Z", "datePublished": "2026-09-09T11:20:58.257Z", "dateUpdated": "2026-09-18T17:23:09.879Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2026-09-09T11:20:58.257Z"}, "datePublic": "2026-08-26T00:00:00.000Z", "title": "Siyuan before v3.8.2 Information Disclosure via Export Preview", "descriptions": [{"lang": "en", "value": "Siyuan before v3.8.2 fails to apply publish-access filtering to embedded blocks before rendering in the /api/export/preview and /api/lute/copyStdMarkdown endpoints. Attackers with reader access can retrieve the full rendered content of private, hidden, or publish-disabled blocks by accessing public documents containing embed queries that select those blocks."}], "problemTypes": [{"descriptions": [{"lang": "en", "description": "Authorization Bypass Through User-Controlled Key", "cweId": "CWE-639", "type": "CWE"}]}], "affected": [{"vendor": "siyuan-note", "product": "siyuan", "defaultStatus": "unaffected", "packageURL": "pkg:golang/github.com/siyuan-note/siyuan", "versions": [{"version": "0", "status": "affected", "versionType": "semver", "lessThan": "3.8.2"}, {"version": "3.8.2", "status": "unaffected", "versionType": "semver"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*", "versionEndExcluding": "3.8.2"}]}]}], "metrics": [{"format": "CVSS", "cvssV4_0": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "LOW", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "baseScore": 7.1, "baseSeverity": "HIGH"}}, {"format": "CVSS", "cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N", "attackVector": "NETWORK", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "availabilityImpact": "NONE", "baseScore": 6.5, "baseSeverity": "MEDIUM"}}], "references": [{"url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-8wx4-fvqw-f5f8", "tags": ["vendor-advisory"], "name": "GitHub Security Advisory (GHSA-8wx4-fvqw-f5f8)"}, {"name": "VulnCheck Advisory: Siyuan before v3.8.2 Information Disclosure via Export Preview", "tags": ["third-party-advisory"], "url": "https://www.vulncheck.com/advisories/siyuan-before-3.8.2-information-disclosure-via-export-preview"}], "x_generator": {"engine": "vulncheck-endgame"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-87809", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-09-18T17:08:58.264762Z"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-09-18T17:23:09.879Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-87809", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-09-18T17:08:58.264762Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-09-18T17:17:56.578Z"}}], "cna": {"title": "Siyuan before v3.8.2 Information Disclosure via Export Preview", "metrics": [{"format": "CVSS", "cvssV4_0": {"version": "4.0", "baseScore": 7.1, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N", "userInteraction": "NONE", "attackComplexity": "LOW", "attackRequirements": "NONE", "privilegesRequired": "LOW", "subIntegrityImpact": "NONE", "vulnIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "vulnConfidentialityImpact": "HIGH"}}, {"format": "CVSS", "cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 6.5, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "NONE", "privilegesRequired": "LOW", "confidentialityImpact": "HIGH"}}], "affected": [{"vendor": "siyuan-note", "product": "siyuan", "versions": [{"status": "affected", "version": "0", "lessThan": "3.8.2", "versionType": "semver"}, {"status": "unaffected", "version": "3.8.2", "versionType": "semver"}], "packageURL": "pkg:golang/github.com/siyuan-note/siyuan", "defaultStatus": "unaffected"}], "datePublic": "2026-08-26T00:00:00.000Z", "references": [{"url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-8wx4-fvqw-f5f8", "name": "GitHub Security Advisory (GHSA-8wx4-fvqw-f5f8)", "tags": ["vendor-advisory"]}, {"url": "https://www.vulncheck.com/advisories/siyuan-before-3.8.2-information-disclosure-via-export-preview", "name": "VulnCheck Advisory: Siyuan before v3.8.2 Information Disclosure via Export Preview", "tags": ["third-party-advisory"]}], "x_generator": {"engine": "vulncheck-endgame"}, "descriptions": [{"lang": "en", "value": "Siyuan before v3.8.2 fails to apply publish-access filtering to embedded blocks before rendering in the /api/export/preview and /api/lute/copyStdMarkdown endpoints. Attackers with reader access can retrieve the full rendered content of private, hidden, or publish-disabled blocks by accessing public documents containing embed queries that select those blocks."}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-639", "description": "Authorization Bypass Through User-Controlled Key"}]}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "3.8.2"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2026-09-09T11:20:58.257Z"}}}, "cveMetadata": {"cveId": "CVE-2026-87809", "state": "PUBLISHED", "dateUpdated": "2026-09-18T17:23:09.879Z", "dateReserved": "2026-09-09T10:30:15.669Z", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "datePublished": "2026-09-09T11:20:58.257Z", "assignerShortName": "VulnCheck"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "packageURL": "pkg:golang/github.com/siyuan-note/siyuan", "product": "siyuan", "vendor": "siyuan-note", "versions": [{"lessThan": "3.8.2", "status": "affected", "version": "0", "versionType": "semver"}, {"status": "unaffected", "version": "3.8.2", "versionType": "semver"}]}], "source": "disclosure@vulncheck.com"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "Siyuan before v3.8.2 fails to apply publish-access filtering to embedded blocks before rendering in the /api/export/preview and /api/lute/copyStdMarkdown endpoints. Attackers with reader access can retrieve the full rendered content of private, hidden, or publish-disabled blocks by accessing public documents containing embed queries that select those blocks."}], "id": "CVE-2026-87809", "lastModified": "2026-09-18T18:17:33.600", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 6.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N", "version": "3.1"}, "exploitabilityScore": 2.8, "impactScore": 3.6, "source": "disclosure@vulncheck.com", "type": "Secondary"}], "cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "NONE", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 7.1, "baseSeverity": "HIGH", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "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": "LOW", "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:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/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": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "NONE", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "disclosure@vulncheck.com", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-87809", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2026-09-18T17:08:58.264762Z", "version": "2.0.3"}}]}, "published": "2026-09-09T12:17:15.650", "references": [{"source": "disclosure@vulncheck.com", "url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-8wx4-fvqw-f5f8"}, {"source": "disclosure@vulncheck.com", "url": "https://www.vulncheck.com/advisories/siyuan-before-3.8.2-information-disclosure-via-export-preview"}], "sourceIdentifier": "disclosure@vulncheck.com", "vulnStatus": "Deferred", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-639"}], "source": "disclosure@vulncheck.com", "type": "Secondary"}]}

{}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,3.8.2)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "3.8.2"}}], "enrichment": {"confidence": 84.0, "confidence_source": "matching", "scores": [{"score": 84.0, "source": "matching"}]}, "original": {"product": "siyuan", "source": "cna", "vendor": "siyuan-note"}, "product": "siyuan", "vendor": "siyuan"}], "created": "2026-09-09T13:00:14.399535+00:00", "updated": "2026-09-13T19:45:17.599189+00:00", "vendors": ["siyuan", "siyuan$PRODUCT$siyuan"]}