Resource exhaustion in Etcd-Io Etcd
CVE-2026-73500
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.
Published · last modified .
EPSS exploit prediction
EPSS: 0.007 (51.1th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 51st percentile — 51.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.004 · newest: 0.007 · change: +0.003
Affected products
- Etcd-Io Etcd — versions < 3.5.33, >= 3.6.0, < 3.6.14, >= 3.7.0-alpha.0, < 3.7.1
Weakness classification (CWE)
References
- github.com/etcd-io/etcd/security/advisories/GHSA-6vch-q96h-7gc3
- github.com/etcd-io/etcd/pull/22130
- github.com/etcd-io/etcd/commit/2e07efce9745004eb4773cffaada9b5cdf77cff2
- github.com/etcd-io/etcd/commit/89ff6d50796049d4f1136915ba21504b76e7e372
- github.com/etcd-io/etcd/commit/8e4dd0679a2c6b095d2a32a749fda2521c7809a3
- github.com/etcd-io/etcd/commit/f73cba7d920019f91a1ea1f6697833e42731f057
- github.com/etcd-io/etcd/releases/tag/v3.5.33
- github.com/etcd-io/etcd/releases/tag/v3.6.14
- github.com/etcd-io/etcd/releases/tag/v3.7.1