CVE-2026-73500: etcd-io etcd

Vulnerability summary

CVE-2026-73500 is a high (CVSS 8.7) vulnerability in etcd-io etcd. EPSS estimates a 0.70% chance of exploitation in the next 30 days, higher than 52.1% of scored vulnerabilities.

Timeline

1. 12-08-2026
   PublishedVulnerability first disclosed.
2. 13-08-2026
   Last modifiedVulnerability information updated.

Description

etcd is a distributed key-value store for the data of a distributed system. Prior to versions 3.5.33, 3.6.14, and 3.7.1, a network attacker who can reach an etcd TLS listener can open many TCP connections and never send a ClientHello. In client/pkg/transport/listener_tls.go, each connection handled by tlsListener.acceptLoop spawns a goroutine that blocks indefinitely inside tls.Conn.Handshake() and remains tracked in the pending map. Unbounded goroutine and map growth can exhaust memory in the etcd process, causing loss of availability for the cluster and, when etcd backs Kubernetes, the control plane. This issue is fixed in versions 3.5.33, 3.6.14, and 3.7.1.

• CWE-770Allocation of Resources Without Limits or ThrottlingThe product allocates a reusable resource or group of resources on behalf of an actor without imposing any intended restrictions on the size or number of resources that can be allocated.