{"vulnerability": "cve-2026-86062", "sightings": [{"uuid": "29b59145-e461-4257-a18c-be4388dee91a", "vulnerability_lookup_origin": "1a89b78e-f703-45f3-bb86-59eb712668bd", "author": "86ecb4e1-bb32-44d5-9f39-8a4673af8385", "vulnerability": "CVE-2026-86062", "type": "published-proof-of-concept", "source": "https://github.com/HKUDS/LightRAG/security/advisories/GHSA-xpjq-3w4w-w5wr", "content": "", "creation_timestamp": "2026-09-22T22:35:14.140584Z"}, {"uuid": "dca40945-8cd5-4437-9397-71041a9aa8be", "vulnerability_lookup_origin": "1a89b78e-f703-45f3-bb86-59eb712668bd", "author": "9f56dd64-161d-43a6-b9c3-555944290a09", "vulnerability": "CVE-2026-86062", "type": "seen", "source": "https://gist.github.com/alon710/bf969bdec8772c71ac789467bc649eb3", "content": "# CVE-2026-86062: CVE-2026-86062: Stored Cross-Site Scripting (XSS) in HKUDS LightRAG WebUI Chat Renderer\n\n> **CVSS Score:** 6.1\n> **Published:** 2026-09-22\n> **Full Report:** https://cvereports.com/reports/CVE-2026-86062\n\n## Summary\nHKUDS LightRAG, an open-source retrieval-augmented generation (RAG) framework, is vulnerable to Stored Cross-Site Scripting (XSS) in its WebUI chat rendering component prior to version 1.5.5. Unsanitized document content ingested into the vector database can propagate through the LLM response pipeline and execute malicious HTML or active JavaScript payloads inside the administrator's WebUI session. Because the application stores sensitive access keys in browser storage, successful exploitation allows complete API token extraction and administrative session hijacking.\n\n## TL;DR\nA Stored XSS vulnerability in LightRAG WebUI prior to v1.5.5 allows attackers to execute arbitrary JavaScript in the victim's browser session by poisoning documents ingested into the RAG knowledge base. This can lead to the exfiltration of the administrative LIGHTRAG-API-TOKEN from local storage, granting full remote control over the API.\n\n## Exploit Status: POC\n\n## Technical Details\n\n- **CWE Identifier**: CWE-79 (Improper Neutralization of Input During Web Page Generation)\n- **Attack Vector**: Network / Client Interaction (UI-Required)\n- **CVSS v3.1 Score**: 6.1 (Medium Severity)\n- **Exploit Status**: Proof of Concept (PoC) documented in official advisories\n- **CISA KEV Status**: Not Listed\n- **Remediation**: Upgrade to v1.5.5 or apply custom rehype-sanitize configurations\n\n## Affected Systems\n\n- HKUDS LightRAG WebUI\n- **LightRAG**: < 1.5.5 (Fixed in: `1.5.5`)\n\n## Mitigation\n\n- Upgrade LightRAG to version 1.5.5 or higher to apply native HTML sanitization patches.\n- Deploy a Content Security Policy (CSP) header on the WebUI web server to restrict inline script execution.\n- Sanitize documents during the ingestion pipeline to strip raw HTML tags before they are indexed in the vector database.\n\n**Remediation Steps:**\n1. Identify all active installations of LightRAG WebUI running versions prior to v1.5.5.\n2. Pull the patched version from the official repository or update the dependency configuration to point to version 1.5.5.\n3. Verify the update by inspecting the build files and checking for the presence of the `rehype-sanitize` dependency inside `package.json`.\n4. Rotate all active `LIGHTRAG-API-TOKEN` values to invalidate any tokens that may have been accessed prior to the upgrade.\n\n## References\n\n- [NVD CVE-2026-86062 Detail](https://nvd.nist.gov/vuln/detail/CVE-2026-86062)\n- [GitHub Security Advisory GHSA-xpjq-3w4w-w5wr](https://github.com/HKUDS/LightRAG/security/advisories/GHSA-xpjq-3w4w-w5wr)\n- [GitHub Pull Request 3437](https://github.com/HKUDS/LightRAG/pull/3437)\n- [LightRAG Release v1.5.5](https://github.com/HKUDS/LightRAG/releases/tag/v1.5.5)\n\n\n---\n*Generated by [CVEReports](https://cvereports.com/reports/CVE-2026-86062) - Automated Vulnerability Intelligence*", "creation_timestamp": "2026-09-23T07:31:38.079150Z"}]}