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.
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.