LookyLoo - PlaywrightCapture permits access to local files and internal network resources during page capture

Summary

PlaywrightCapture is a simple replacement for splash using playwright. Prior to 1.39.6, PlaywrightCapture did not sufficiently restrict navigations and resource requests initiated by rendered pages. An attacker-controlled page could abuse browser-side redirection mechanisms, such as window.location.href, to make the capture process open file:// URLs or request resources hosted on private, loopback, link-local, or otherwise non-public IP addresses. In deployments where PlaywrightCapture processes untrusted URLs, this could allow a remote attacker to perform server-side request forgery against internal services or attempt to access local files from the capture environment. Depending on what capture artifacts are generated and exposed, responses from those resources could potentially be leaked through screenshots, saved page content, logs, or other capture outputs. This vulnerability is fixed in 1.39.6.