CVE-2026-66913
MediumCVSS 6.9Exploitation Probability (EPSS)
Low risk17th percentile - higher than 17% of all known CVEs
Summary
Lookyloo does not enforce limits on the decompressed size of uploaded capture archives and compressed HAR files. An attacker can submit a crafted archive that expands to a very large size, exhausting memory and causing denial of service.
Risk Assessment
Repeated exploitation could cause persistent denial of service, making the Lookyloo instance unavailable until restarted.
Recommendation
Update Lookyloo to a version containing the fix, which introduces a 1 GB uncompressed size limit and size-limited gzip/zlib decompression.
Other vulnerabilities in Lookyloo
See all- CVE-2025-65095Critical
Lookyloo prior to version 1.35.1 has potential cross-site scripting on index and tree pages. This issue has been patched in version 1.35.1.
- CVE-2026-73210Medium
A Server-Side Request Forgery (SSRF) vulnerability was found in Lookyloo's PlaywrightCapture when the only_global_lookup option is enabled. Favicon retrieval was performed outside the browser request-routing protections, allowing an attacker to send HTTP requests to internal resources (e.g., loopback, private IPs) via a crafted web page. The patch introduces a common URL validation routine for favicon retrieval, rejecting non-public destinations.
- CVE-2025-66460Medium
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, Lookyloo passed improperly escaped values to cells rendered in datatables using the orthogonal-data feature. It is definitely exploitable from the popup view, but it is most probably also exploitable in many other places. This vulnerability is fixed in 1.35.3.
- CVE-2025-66459Medium
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.
- CVE-2025-66458Medium
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.
Original NVD description (English source)
Lookyloo did not enforce limits on the decompressed size of uploaded capture archives and compressed HAR files. An attacker could submit a specially crafted ZIP, gzip, or zlib-compressed capture containing data that expands to a very large size during processing. Because the application decompressed this content directly in memory without first limiting the output size, processing the malicious capture could exhaust available memory, terminate a web or worker process, or make the Lookyloo instance unavailable. The vulnerability affects both full Lookyloo capture archive imports and API submissions containing gzip-compressed HAR data. Repeated exploitation could cause a persistent denial-of-service condition until the affected processes or instance are restarted. The patch introduces: * A 1 GB cumulative uncompressed-size limit for imported capture archives. * Size-limited gzip and zlib decompression for compressed HAR files. * Explicit detection and handling of suspected zip bombs. * An HTTP 400 response when an oversized compressed HAR file is submitted through the API.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

