{"id":"CVE-2026-100634","state":"PUBLISHED","title":"SiYuan before v3.8.4 Missing Authorization via siyuan-send-windows","description":"SiYuan before v3.8.4 does not validate the sender or restrict recipients in the 'siyuan-send-windows' IPC handler of the Electron main process (app/electron/main.js). The handler ignores event.sender and forwards any received payload to every BrowserWindow returned by BrowserWindow.getAllWindows(), including windows belonging to other opened workspaces. A renderer connected to an attacker-controlled remote kernel can therefore send {cmd: \"lockscreenByMode\"} and have it delivered across the workspace boundary; a sibling workspace window whose lockScreenMode is set to 1 invokes lockScreen(). Repeated messages allow the remote workspace to repeatedly lock unrelated local workspace windows, causing a limited denial of service. No confidentiality, integrity, or code-execution impact was observed.","publishedAt":"2026-09-26T13:23:09.166Z","updatedAt":"2026-10-08T15:51:25.360Z","severity":{"score":5.3,"label":"Medium","version":"4.0","vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:L","source":"VulnCheck"},"assigner":"VulnCheck","products":["siyuan-note siyuan"],"affected":[{"vendor":"siyuan-note","product":"siyuan","packageURL":"pkg:golang/github.com/siyuan-note/siyuan/kernel","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"3.8.4","versionType":"semver"},{"version":"3.8.4","status":"unaffected","versionType":"semver"}]}],"references":["https://github.com/siyuan-note/siyuan/security/advisories/GHSA-wxp7-xpq8-8xpm","https://github.com/siyuan-note/siyuan/commit/8641553a1f07374001902d3ce773285db1292b2d","https://www.vulncheck.com/advisories/siyuan-before-3.8.4-missing-authorization-via-siyuan-send-windows"],"weaknesses":["CWE-862"],"ingestedAt":"2026-10-29T20:10:13.529Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/100xxx/CVE-2026-100634.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-100634","state":"PUBLISHED","datePublished":"2026-09-26T13:23:09.166Z","dateUpdated":"2026-10-08T15:51:25.360Z","assignerShortName":"VulnCheck","assignerOrgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateReserved":"2026-09-26T02:31:42.100Z"},"containers":{"cna":{"title":"SiYuan before v3.8.4 Missing Authorization via siyuan-send-windows","descriptions":[{"lang":"en","value":"SiYuan before v3.8.4 does not validate the sender or restrict recipients in the 'siyuan-send-windows' IPC handler of the Electron main process (app/electron/main.js). The handler ignores event.sender and forwards any received payload to every BrowserWindow returned by BrowserWindow.getAllWindows(), including windows belonging to other opened workspaces. A renderer connected to an attacker-controlled remote kernel can therefore send {cmd: \"lockscreenByMode\"} and have it delivered across the workspace boundary; a sibling workspace window whose lockScreenMode is set to 1 invokes lockScreen(). Repeated messages allow the remote workspace to repeatedly lock unrelated local workspace windows, causing a limited denial of service. No confidentiality, integrity, or code-execution impact was observed."}],"affected":[{"vendor":"siyuan-note","product":"siyuan","packageURL":"pkg:golang/github.com/siyuan-note/siyuan/kernel","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThan":"3.8.4","versionType":"semver"},{"version":"3.8.4","status":"unaffected","versionType":"semver"}]}],"references":[{"url":"https://github.com/siyuan-note/siyuan/security/advisories/GHSA-wxp7-xpq8-8xpm","tags":["vendor-advisory"],"name":"GitHub Security Advisory (GHSA-wxp7-xpq8-8xpm)"},{"url":"https://github.com/siyuan-note/siyuan/commit/8641553a1f07374001902d3ce773285db1292b2d","tags":["patch"],"name":"Patch Commit"},{"url":"https://www.vulncheck.com/advisories/siyuan-before-3.8.4-missing-authorization-via-siyuan-send-windows","name":"VulnCheck Advisory: SiYuan before v3.8.4 Missing Authorization via siyuan-send-windows","tags":["third-party-advisory"]}],"metrics":[{"format":"CVSS","cvssV4_0":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:L","attackVector":"NETWORK","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","userInteraction":"PASSIVE","vulnConfidentialityImpact":"NONE","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"LOW","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"LOW","baseScore":5.3,"baseSeverity":"MEDIUM"}},{"format":"CVSS","cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:N/A:L","attackVector":"NETWORK","attackComplexity":"LOW","privilegesRequired":"NONE","userInteraction":"REQUIRED","scope":"CHANGED","confidentialityImpact":"NONE","integrityImpact":"NONE","availabilityImpact":"LOW","baseScore":4.7,"baseSeverity":"MEDIUM"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-862","lang":"en","description":"Missing Authorization","type":"CWE"}]}],"providerMetadata":{"shortName":"VulnCheck","orgId":"83251b91-4cc7-4094-a5c7-464a1b83ea10","dateUpdated":"2026-10-08T15:51:25.360Z"},"datePublic":"2026-09-11T00:00:00.000Z","cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*","versionEndExcluding":"3.8.4"}]}]}],"credits":[{"lang":"en","value":"rexpository","type":"reporter"}],"x_generator":{"engine":"vulncheck-endgame"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/siyuan-note/siyuan/security/advisories/GHSA-wxp7-xpq8-8xpm","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-09-30T13:01:06.934595Z","id":"CVE-2026-100634","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-09-30T13:01:30.819Z"}}]}}}