bug(frontend): XSS vulnerability in chatbot.js — inline code and bold text not HTML-escaped before innerHTML

[AayushBaniya2006]

Summary

The frontend chatbot renders assistant output through innerHTML after passing it through
formatMarkdown() in docs_scripts/chatbot.js.

Fenced code blocks are escaped via escapeHtml(), but inline code and bold text
substitutions insert captured groups directly into HTML without escaping. Raw HTML outside
any markdown marker also survives into the DOM.

Evidence

Unsafe substitutions:

• Inline code (line 767): formatted = formatted.replace(/([^\n]+)/g, '$1');`
• Bold text (line 773): formatted = formatted.replace(/\*\*(.*?)\*\*/g, '<strong>$1</strong>');

innerHTML sinks:

• Streaming path: docs_scripts/chatbot.js:609
• Non-streaming path: docs_scripts/chatbot.js:830

Existing escaping (used for fenced code blocks only):

• escapeHtml() at docs_scripts/chatbot.js:975

Impact

If the model returns text containing HTML like <img src=x onerror=alert(1)>, it is
inserted into the DOM unsanitized via innerHTML.

Expected Fix

At minimum, apply escapeHtml() to captured groups in the inline code and bold regex
replacements. A more comprehensive fix would escape all raw text before selectively
re-introducing safe markdown formatting.

[kenjoel]

/assign