DeepChat: Persistent DOM XSS via HTML Entity Encoding in `` SVG Rendering (Bypass of `svgSanitizer.ts`)_CVE-2026-43900

{
    "lastseen": "",
    "description": "DeepChat is an open-source artificial intelligence agent platform that unifies models, tools, and agents. Prior to v1.0.4-beta.1, a Cross-Site Scripting (XSS) vulnerability exists due to a discrepancy between the backend validation layer and the frontend browser rendering engine. The SVGSanitizer (src/main/lib/svgSanitizer.ts) restricts script execution by scrubbing javascript: protocols using plain-text regular expressions. However, it fails to account for HTML entity decoding prior to Vue's v-html DOM insertion inside the SvgArtifact.vue component. By feeding an SVG artifact with obfuscated entities (e.g., javascript:alert(1)), an attacker can completely bypass the sanitizer, culminating in arbitrary JavaScript execution when a victim interacts with the rendered SVG Element. This vulnerability is fixed in v1.0.4-beta.1.",
    "published": "2026-05-11T21:42:19.927Z",
    "modified": "2026-05-11T21:42:19.927Z",
    "type": "cve",
    "title": "DeepChat: Persistent DOM XSS via HTML Entity Encoding in `<antArtifact>` SVG Rendering (Bypass of `svgSanitizer.ts`)",
    "source": "GitHub_M",
    "references": "https://github.com/ThinkInAIXYZ/deepchat/security/advisories/GHSA-7r59-67v3-3mgp",
    "id": "CVE-2026-43900",
    "bulletinFamily": "",
    "cwe": [
        "CWE-79"
    ],
    "cvelist": null,
    "sourceData": "ThinkInAIXYZ deepchat < 1.0.4-beta.1",
    "sourceHref": "",
    "cvss": {
        "score": 9.3,
        "severity": "CRITICAL",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
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        "baseScore": 0,
        "baseSeverity": "",
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        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
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            "baseScore": 0,
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        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "deepchat",
    "version": "< 1.0.4-beta.1",
    "vendor": "ThinkInAIXYZ",
    "ai_description": "Cross-Site Scripting (XSS) vulnerability due to discrepancy between backend validation and frontend rendering",
    "ai_severity": "Critical",
    "ai_vendor": "ThinkInAIXYZ",
    "ai_product": "DeepChat",
    "ai_version": "< 1.0.4-beta.1",
    "ai_score": 9.3
}