CVE-2026-73500etcd: `tlsListener.acceptLoop` spawns unbounded handshake goroutines with no deadline
Updated under an hour ago ()
Does this affect you?
It affects etcd-io etcd. Add what you run to find out whether that includes you.
No exploitation reported and no EPSS estimate yet.
Do this next
Free account, 1 product
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.
- CVSS
- 8.7 HIGH (v4.0, CNA)CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
- Weakness (CWE)
- CWE-770
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- GitHub_M
- NVD analysis
- Awaiting Analysis
- Record last updated
- Aug 13, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
etcd-io etcd etcd_io:etcd (from the name) | before 3.5.33; from 3.6.0, < 3.6.14; from 3.7.0-alpha.0, < 3.7.1 | CNA record |
References
- https://github.com/etcd-io/etcd/security/advisories/GHSA-6vch-q96h-7gc3x-refsource-confirm
- https://github.com/etcd-io/etcd/pull/22130x-refsource-misc
- https://github.com/etcd-io/etcd/commit/2e07efce9745004eb4773cffaada9b5cdf77cff2x-refsource-misc
- https://github.com/etcd-io/etcd/commit/89ff6d50796049d4f1136915ba21504b76e7e372x-refsource-misc
- https://github.com/etcd-io/etcd/commit/8e4dd0679a2c6b095d2a32a749fda2521c7809a3x-refsource-misc
- https://github.com/etcd-io/etcd/commit/f73cba7d920019f91a1ea1f6697833e42731f057x-refsource-misc
- https://github.com/etcd-io/etcd/releases/tag/v3.5.33x-refsource-misc
- https://github.com/etcd-io/etcd/releases/tag/v3.6.14x-refsource-misc
- https://github.com/etcd-io/etcd/releases/tag/v3.7.1x-refsource-misc
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.