Security context
What an agent needs to avoid regressing past fixes and find the next vuln in this repo.
mcp-ui-org/mcp-ui
main @ 33de6b6
3
Fixes
0
CVEs
HIGH
Peak severity
Highlights
Cross-Origin Communication: 2 prior fixes. Scrutinize any change in this area.
packages/client/scripts/proxy/index.html: most-fixed (2 issues). Treat as high-risk during review.
1 high-severity fix in this history; regressions here are high-impact.
Recurring patterns
The bug types that recur here, drawn from past fixes, not open vulnerabilities.
Cross-Origin Communication: The client proxy relay utilized postMessage with a wildcard ('*') target origin and lacked origin verification, allowing arbitrary external domains to intercept and inject messages. Ongoing development in message relays must strictly validate both event.origin and postMessage target origins.
Sandbox Escape: Unsanitized URI-list processing permitted loading unsafe schemas (e.g., 'javascript:') into iframes. This allows a malicious payload to bypass sandbox controls and execute scripts in the context of the parent application window.