CVE-2025-66458: Lookyloo

Medium severity, CVSS 6.1. EPSS: 0.2% chance of exploitation in the next 30 days.

Lookyloo is a web interface that allows users to capture a website page and then display a tree of domains that call each other. Prior to 1.35.3, there are multiple XSS due to unsafe use of f-strings in Markup. The issue requires a malicious 3rd party server responding with a JSON document containing JS code in a script element. This vulnerability is fixed in 1.35.3.

Affected products

• Lookyloo Lookyloo: before 1.35.3 (fixed in 1.35.3)

Published 2025-12-02. Last modified 2026-09-25.