CVE-2026-86062

LightRAG: Stored Cross-Site Scripting (XSS) in the LightRAG WebUI chat/answer renderer via ingested content

Published Sep 22, 2026 CVSS 3.1 · 6.1 Medium EPSS < 1% KEV · Not listed
Description
LightRAG provides simple and fast retrieval-augmented generation. Prior to 1.5.5, lightrag_webui/src/components/retrieval/ChatMessage.tsx renders answer and thinking content with react-markdown, rehypeRaw, and skipHtml=false without an HTML sanitizer. An attacker who can add a document can store raw HTML that is returned through the query path and rendered as active content by MessageMarkdown. A user who later retrieves the content can execute attacker-controlled JavaScript through elements such as an iframe srcdoc; the additional Mermaid securityLevel: loose rendering path also injects generated SVG through innerHTML. The script runs in the LightRAG WebUI origin and can read the API token in localStorage and perform API actions as the victim. This issue is fixed in version 1.5.5.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Github GHSA Github GHSA GHSA-xpjq-3w4w-w5wr lightrag-hku: Stored Cross-Site Scripting (XSS) in the LightRAG WebUI chat/answer renderer via ingested content
History
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'poc', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Hkuds
Hkuds lightrag
Vendors & Products Hkuds
Hkuds lightrag
Type Values Removed Values Added
Description LightRAG provides simple and fast retrieval-augmented generation. Prior to 1.5.5, lightrag_webui/src/components/retrieval/ChatMessage.tsx renders answer and thinking content with react-markdown, rehypeRaw, and skipHtml=false without an HTML sanitizer. An attacker who can add a document can store raw HTML that is returned through the query path and rendered as active content by MessageMarkdown. A user who later retrieves the content can execute attacker-controlled JavaScript through elements such as an iframe srcdoc; the additional Mermaid securityLevel: loose rendering path also injects generated SVG through innerHTML. The script runs in the LightRAG WebUI origin and can read the API token in localStorage and perform API actions as the victim. This issue is fixed in version 1.5.5.
Title LightRAG: Stored Cross-Site Scripting (XSS) in the LightRAG WebUI chat/answer renderer via ingested content
Weaknesses CWE-79
References
Metrics cvssV3_1

{'score': 6.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Sep 22, 2026, 6:17 PM
Reserved
Sep 4, 2026, 7:34 PM
Status
Deferred
Published
Sep 22, 2026, 5:17 PM
Modified
Sep 22, 2026, 7:16 PM