CVE-2026-43980: malla: Stored XSS via Meshtastic node names in multiple frontend pages

Node names (long_name, short_name) received via MQTT are stored in SQLite without sanitization and rendered into the DOM without escaping. Any participant on a public Meshtastic MQTT broker can set a malicious node name that executes JavaScript in the browser of every Malla dashboard visitor.

Affected files:

• src/malla/templates/traceroute_graph.html (line ~832)
• src/malla/templates/map.html (lines ~945, 1078)
• src/malla/templates/packet_detail.html (lines ~1402, 1452)
• src/malla/static/js/relay_node_analysis.js (line ~124)

Steps to reproduce

1. Publish a Meshtastic NODEINFO_APP packet to any public MQTT broker with long_name set to a HTML entity i.e <img src=x onerror=alert(1)>
2. Wait for malla-capture to store it
3. Open the dashboard

Impact

Allows unauthenticated remote attackers to execute arbitrary JavaScript in the browser, such as:

• Phishing overlays
• Force redirect to malicious websites
• Injection of arbitrary third-party scripts (no CSP restrictions)
• Browser resource abuse
• Persistent dashboard denial of service