{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-75916",
        "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "state": "PUBLISHED",
        "assignerShortName": "VulnCheck",
        "dateReserved": "2026-08-18T15:05:54.226Z",
        "datePublished": "2026-08-19T14:01:50.370Z",
        "dateUpdated": "2026-10-08T15:51:43.765Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
                "shortName": "VulnCheck",
                "dateUpdated": "2026-10-08T15:51:43.765Z"
            },
            "datePublic": "2026-08-05T00:00:00.000Z",
            "title": "SiYuan XSS-to-RCE via unescaped block metadata in hint popup",
            "descriptions": [
                {
                    "lang": "en",
                    "value": "SiYuan through 3.7.3 contains a cross-site scripting vulnerability in the '((' block-reference autocomplete hint popup. In genHintItemHTML() (app/src/protyle/hint/extend.ts), a candidate block's name, alias, and memo fields are concatenated into the popup's HTML without escaping. An attacker who can set these metadata fields on a block can inject a self-firing payload (e.g. <img src=x onerror=...>) that executes automatically when a victim types '((' followed by a search term that surfaces the crafted block. Because SiYuan's Electron windows run with nodeIntegration enabled, contextIsolation disabled, and no CSP, the injected script gains require('child_process') access, allowing the XSS to escalate to arbitrary OS command execution."
                }
            ],
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "description": "Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')",
                            "cweId": "CWE-79",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "vendor": "siyuan-note",
                    "product": "siyuan",
                    "defaultStatus": "affected",
                    "packageURL": "pkg:golang/github.com/siyuan-note/siyuan/kernel"
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:a:b3log:siyuan:-:*:*:*:*:*:*:*"
                                }
                            ]
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "format": "CVSS",
                    "cvssV4_0": {
                        "version": "4.0",
                        "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H",
                        "attackVector": "LOCAL",
                        "attackComplexity": "LOW",
                        "attackRequirements": "NONE",
                        "privilegesRequired": "NONE",
                        "userInteraction": "PASSIVE",
                        "vulnConfidentialityImpact": "HIGH",
                        "vulnIntegrityImpact": "HIGH",
                        "vulnAvailabilityImpact": "HIGH",
                        "subConfidentialityImpact": "HIGH",
                        "subIntegrityImpact": "HIGH",
                        "subAvailabilityImpact": "HIGH",
                        "baseScore": 9.3,
                        "baseSeverity": "CRITICAL"
                    }
                },
                {
                    "format": "CVSS",
                    "cvssV3_1": {
                        "version": "3.1",
                        "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H",
                        "attackVector": "LOCAL",
                        "attackComplexity": "LOW",
                        "privilegesRequired": "NONE",
                        "userInteraction": "REQUIRED",
                        "scope": "CHANGED",
                        "confidentialityImpact": "HIGH",
                        "integrityImpact": "HIGH",
                        "availabilityImpact": "HIGH",
                        "baseScore": 8.6,
                        "baseSeverity": "HIGH"
                    }
                }
            ],
            "references": [
                {
                    "url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-5prr-vgxq-69g9",
                    "tags": [
                        "vendor-advisory"
                    ],
                    "name": "GitHub Security Advisory (GHSA-5prr-vgxq-69g9)"
                },
                {
                    "name": "VulnCheck Advisory: SiYuan XSS-to-RCE via unescaped block metadata in hint popup",
                    "tags": [
                        "third-party-advisory"
                    ],
                    "url": "https://www.vulncheck.com/advisories/siyuan-xss-to-rce-via-unescaped-block-metadata-in-hint-popup"
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "value": "alham-rizvi",
                    "type": "reporter"
                },
                {
                    "lang": "en",
                    "value": "hey-raghav",
                    "type": "analyst"
                }
            ],
            "x_generator": {
                "engine": "vulncheck-endgame"
            }
        },
        "adp": [
            {
                "references": [
                    {
                        "url": "https://github.com/siyuan-note/siyuan/security/advisories/GHSA-5prr-vgxq-69g9",
                        "tags": [
                            "exploit"
                        ]
                    }
                ],
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-08-21T19:21:47.693296Z",
                                "id": "CVE-2026-75916",
                                "options": [
                                    {
                                        "Exploitation": "poc"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "total"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-08-21T19:22:16.263Z"
                }
            }
        ]
    }
}