{"id":"CVE-2026-43900","aliases":["EUVD-2026-29337","GHSA-7r59-67v3-3mgp"],"status":"published","title":"DeepChat: Persistent DOM XSS via HTML Entity Encoding in `\u003cantArtifact\u003e` SVG Rendering (Bypass of `svgSanitizer.ts`)","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., j\u0026#x61;vascript: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.","severity":{"version":"3.1","score":9.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N","level":"critical","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-09","score":0.00373,"percentile":0.31443,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-79"],"published":"2026-05-11T21:42:19Z","modified":"2026-10-28T02:30:23Z","products":[{"vendor":"thinkinaixyz","product":"deepchat"}],"references":[{"url":"https://github.com/ThinkInAIXYZ/deepchat/security/advisories/GHSA-7r59-67v3-3mgp","tags":["x_refsource_CONFIRM","exploit","advisory"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/43xxx/CVE-2026-43900.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-43900","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-43900","title":"DeepChat: Persistent DOM XSS via HTML Entity Encoding in `\u003cantArtifact\u003e` SVG Rendering (Bypass of `svgSanitizer.ts`)","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., j\u0026#x61;vascript: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.","status":"published","published":"2026-05-11T21:42:19.927Z","modified":"2026-05-12T13:18:37.241Z","cvss":[{"version":"3.1","score":9.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N","level":"critical","assessor":"cna"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T13:37:25.103021Z"}],"euvd":[{"id":"EUVD-2026-29337","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., j\u0026#x61;vascript: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.","status":"published","published":"2026-05-11T21:42:19Z","modified":"2026-05-12T13:18:37Z","cvss":[{"version":"3.1","score":9.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N","level":"critical"}],"updated_at":"2026-11-02T19:04:37.66514Z"}],"nvd":[{"id":"CVE-2026-43900","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., j\u0026#x61;vascript: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.","status":"published","published":"2026-05-11T23:20:21.557Z","modified":"2026-10-26T18:10:00.173Z","cvss":[{"version":"3.1","score":9.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N","level":"critical","assessor":"secondary"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T14:12:18.239974Z"}],"osv":[{"id":"CVE-2026-43900","title":"DeepChat: Persistent DOM XSS via HTML Entity Encoding in `\u003cantArtifact\u003e` SVG Rendering (Bypass of `svgSanitizer.ts`)","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., j\u0026#x61;vascript: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.","status":"published","published":"2026-05-11T21:42:19.927Z","modified":"2026-10-28T02:30:23.141273684Z","cvss":[{"version":"3.1","score":9.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N","level":"critical"}],"cwes":["CWE-79"],"updated_at":"2026-11-02T15:45:04.820169Z"}]}}