CVE-2025-66459 Lookyloo vulnerable to XSS due to unescaped error message passed to innerHTML
Attacker can execute arbitrary JavaScript via unescaped error messages when capturing malicious URLs in Lookyloo.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- None listed
What is CVE-2025-66459?
CVE-2025-66459 is a medium-severity cross-site scripting vulnerability in lookyloo, published on 2 Dec 2025. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
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, a XSS vulnerability can be triggered when a user submits a list of URLs to capture, one of them contains a HTML element, and the capture fails. Then, the error field is populated with an error message that contains the bad URL they tried to capture, triggering the XSS. This vulnerability is fixed in 1.35.3.
Weakness: CWE-79
Which versions are affected by CVE-2025-66459?
It affects 1 product.
Products include Lookyloo Lookyloo.
How do I fix CVE-2025-66459?
No fix has been published for CVE-2025-66459 yet. Limit exposure of the affected software until one is available.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2025-66459 being exploited?
There is no known exploitation of CVE-2025-66459 in the wild and no public exploit code.
Other vulnerabilities in lookyloo
Sources
Also known as GHSA-hvmh-j2jx-48wg.