CVE-2026-66296 Reflected XSS in oaskit's default HTML error handler

Improper Neutralization of Input During Web Page Generation XSS vulnerability in lud oaskit allows reflected cross-site scripting via the default HTML error handler. Oaskit.ErrorHandler.Default.formatreason/4 and Oaskit.ErrorHandler.Default.reasontohtml/1 in lib/oaskit/errorhandler/default.ex...