{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-100635", "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "state": "PUBLISHED", "assignerShortName": "VulnCheck", "dateReserved": "2026-09-26T02:31:42.100Z", "datePublished": "2026-09-26T13:23:09.854Z", "dateUpdated": "2026-09-26T13:23:09.854Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10", "shortName": "VulnCheck", "dateUpdated": "2026-09-26T13:23:09.854Z"}, "datePublic": "2026-09-11T00:00:00.000Z", "title": "SiYuan before v3.8.4 Authentication Bypass via Plaintext Session Cookie", "descriptions": [{"lang": "en", "value": "SiYuan before v3.8.4 contains an authentication bypass vulnerability in the publish service where session cookies are issued without Secure or SameSite attributes over plaintext HTTP connections. An on-path attacker can observe a valid publish-visitor-session-id cookie from a Basic Auth exchange and replay it to access authenticated publish endpoints without knowing the account password."}], "problemTypes": [{"descriptions": [{"lang": "en", "description": "Cleartext Transmission of Sensitive Information", "cweId": "CWE-319", "type": "CWE"}]}], "affected": [{"vendor": "siyuan-note", "product": "siyuan", "defaultStatus": "unaffected", "packageURL": "pkg:npm/siyuan-note/siyuan", "versions": [{"version": "0", "status": "affected", "versionType": "semver", "lessThan": "3.8.4"}, {"version": "3.8.4", "status": "unaffected", "versionType": "semver"}]}], "metrics": [{"format": "CVSS", "cvssV4_0": {"version": "4.0", "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N", "attackVector": "NETWORK", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "privilegesRequired": "NONE", "userInteraction": "NONE", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "NONE", "vulnAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "subAvailabilityImpact": "NONE", "baseScore": 8.2, "baseSeverity": "HIGH"}}, {"format": "CVSS", "cvssV3_1": {"version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N", "attackVector": "NETWORK", "attackComplexity": "HIGH", "privilegesRequired": "NONE", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "availabilityImpact": "NONE", "baseScore": 5.9, "baseSeverity": "MEDIUM"}}], "references": [{"url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-7j37-4gq6-wm7m", "tags": ["vendor-advisory"], "name": "GitHub Security Advisory (GHSA-7j37-4gq6-wm7m)"}, {"url": "https://github.com/siyuan-note/siyuan/commit/79d47867b106467c951475a9193455b48d1f3682", "tags": ["patch"], "name": "Patch Commit"}, {"url": "https://github.com/siyuan-note/siyuan/commit/ff4d215f78a8d6e6db6052be18b5f9f4db9c7d68", "tags": ["patch"], "name": "Patch Commit"}, {"name": "VulnCheck Advisory: SiYuan before v3.8.4 Authentication Bypass via Plaintext Session Cookie", "tags": ["third-party-advisory"], "url": "https://www.vulncheck.com/advisories/siyuan-before-3.8.4-authentication-bypass-via-plaintext-session-cookie"}], "credits": [{"lang": "en", "value": "rexpository", "type": "reporter"}], "x_generator": {"engine": "vulncheck-endgame"}}}}

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{"created": "2026-09-26T16:00:09.853337+00:00", "updated": "2026-09-26T16:00:09.853345+00:00", "vendors": []}