CVE-2020-15114: 
etcd vulnerability analysis and mitigation

The vulnerability (CVE-2020-15114) affects etcd versions before 3.3.23 and 3.4.10. The etcd gateway, which functions as a simple TCP proxy for basic service discovery and access, contains a vulnerability where it's possible to include the gateway's own address as an endpoint (GitHub Advisory, NVD).

The vulnerability occurs when the gateway address is included as an endpoint in the configuration. This creates a recursive loop where the endpoint continuously requests itself, leading to resource exhaustion. The issue specifically affects the gateway's TCP proxy functionality, which is designed for service discovery and access (GitHub Advisory).

When exploited, this vulnerability results in a denial of service (DoS) condition. The endpoint becomes stuck in a loop of self-requests until there are no more available file descriptors to accept connections on the gateway, effectively rendering the service unavailable (GitHub Advisory, Red Hat).

The vulnerability is considered to have a High severity rating. It can be triggered by including the gateway's own address as an endpoint, which leads to resource exhaustion and subsequent denial of service (GitHub Advisory).

The vulnerability has been patched in etcd versions 3.3.23 and 3.4.10. Users are advised to upgrade to these or later versions to mitigate the issue. Various distributions have also released security updates, including Red Hat OpenStack Platform and Ubuntu (Red Hat, Ubuntu).