Istio is an open platform to connect, manage, and secure microservices. In affected versions ill-formed headers sent to Envoy in certain configurations can lead to unexpected memory access resulting in undefined behavior or crashing. Users are most likely at risk if they have an Istio ingress Gateway exposed to external traffic. This vulnerability has been resolved in versions 1.12.8, 1.13.5, and 1.14.1. Users are advised to upgrade. There are no known workarounds for this issue.