The flaw resides in CoreDNS’s loop detection plugin. An attacker can craft DNS queries that exploit the predictable pseudo‑random number generator used to generate secret query names, causing the plugin to raise a fatal error that terminates the entire DNS server. The outcome is a denial of service that can disrupt all clients relying on that DNS service. The weakness encompasses predictable PRNG use (CWE‑337), uncontrolled resource exhaustion (CWE‑400), and other related vulnerabilities (CWE‑1241, CWE‑770).

CoreDNS, the DNS server software chain used by many container and cloud deployments. Versions earlier than 1.14.2 are affected; the vulnerability was fixed in the 1.14.2 release.

With a CVSS score of 7.5 the vulnerability is considered high severity. The EPSS score is below 1 %, indicating a low probability of current exploitation, and it has not appeared in the CISA Known Exploited Vulnerabilities catalog. The attack vector is inferred to be remote over the network, since an attacker only needs to send a specially crafted DNS query. A single successful request can crash the entire server, making rapid mitigation essential to preserve DNS availability.