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        "cveId": "CVE-2026-100634",
        "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "state": "PUBLISHED",
        "assignerShortName": "VulnCheck",
        "dateReserved": "2026-09-26T02:31:42.100Z",
        "datePublished": "2026-09-26T13:23:09.166Z",
        "dateUpdated": "2026-10-08T15:51:25.360Z"
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                "dateUpdated": "2026-10-08T15:51:25.360Z"
            },
            "datePublic": "2026-09-11T00:00:00.000Z",
            "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."
                }
            ],
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                            "lang": "en",
                            "description": "Missing Authorization",
                            "cweId": "CWE-862",
                            "type": "CWE"
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                    ]
                }
            ],
            "affected": [
                {
                    "vendor": "siyuan-note",
                    "product": "siyuan",
                    "defaultStatus": "unaffected",
                    "packageURL": "pkg:golang/github.com/siyuan-note/siyuan/kernel",
                    "versions": [
                        {
                            "version": "0",
                            "status": "affected",
                            "versionType": "semver",
                            "lessThan": "3.8.4"
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                            "version": "3.8.4",
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                        "attackVector": "NETWORK",
                        "attackComplexity": "LOW",
                        "attackRequirements": "NONE",
                        "privilegesRequired": "NONE",
                        "userInteraction": "PASSIVE",
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                    "url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-wxp7-xpq8-8xpm",
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                                "timestamp": "2026-09-30T13:01:06.934595Z",
                                "id": "CVE-2026-100634",
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