CVE-2026-43900DeepChat: Persistent DOM XSS via HTML Entity Encoding in `<antArtifact>` SVG Rendering (Bypass of `svgSanitizer.ts`)
- 9.3CriticalCVSS base score
- 0.37%Exploitation in 30 daysEPSS · top 68% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- YesPublic exploitsa reference or SSVC says so
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.
Public exploit
An exploit or proof of concept is public: anyone can try it against an unpatched system. A reference of the record is tagged as an exploit. CISA's SSVC rates its exploitation: a proof of concept is public.
Show the exploits1
References tagged exploit1 reference
- https://github.com/ThinkInAIXYZ/deepchat/security/advisories/GHSA-7r59-67v3-3mgp (opens in a new tab)x_refsource_CONFIRMexploit
Timeline
ID reserved
By GitHub_M
- 7 days later
· 7 days later
Published
- 1 day later
· 1 day later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | Critical9.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N |
| NVDNVD · Deferred | 3.1 | Critical9.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N |
- EPSS (exploitation in 30 days)
- 0.37% · top 68% of all CVEs (13 Nov 2026)
- CISA SSVC
- Exploitation: poc · Automatable: no · Technical impact: total
The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.3.
Affected products
- affected < 1.0.4-beta.1
References
References1
- https://github.com/ThinkInAIXYZ/deepchat/security/advisories/GHSA-7r59-67v3-3mgp (opens in a new tab)x_refsource_CONFIRMexploit
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-29337 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-43900)Record last updated .