CVE-2026-55835
MediumCVSS 6.9Exploitation Probability (EPSS)
Low risk23th percentile - higher than 23% of all known CVEs
Summary
Lookyloo prior to version 1.39.4 allows an unauthenticated user to trigger the “report a capture” email on demand (which is expected). The /json/<uuid>/report API endpoint (CaptureReport) incorrectly passes the email and comment parameters, overwriting as_admin. When True, as_admin triggers a search query on a MISP instance (if configured) and adds a list of matching URLs to the email sent to the analyst (not the submitter, so there is no risk of information leakage). This could potentially cause a DoS on the MISP instance.
Risk Assessment
Overloading the MISP instance through forced queries is possible, potentially leading to denial of service for analysts. There is no information leakage risk since the email goes to the analyst.
Recommendation
Update Lookyloo to version 1.39.4 or later. Monitor MISP instance load and consider restricting access to the report endpoint.
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-2026-66913Medium
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.
- 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 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 version 1.39.4, an unauthenticated user can trigger Lookyloo's "report a capture" email on demand (this is expected). The /json/<uuid>/report API endpoint (CaptureReport) is incorrectly passing the email and comment parameters, overwriting as_admin. When True, as_admin will trigger a search query on a MISP instance (if configured) and add a list of matching URLs in the email sent to the analyst (not the submitter, so there is no risk of leaking information) . It could potentially cause a DoS on the MISP instance. This issue has been patched in version 1.39.4.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS