etcd is core infrastructure for Kubernetes; a DoS of etcd can degrade or break cluster control planes and impact many organizations.
CVE-2026-73500
etcd TLS listener can be abused to exhaust memory and cause etcd/Kubernetes control plane DoS
Is CVE-2026-73500 being exploited?
Not confirmed. CVE-2026-73500 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.40% probability of exploitation in the next 30 days.
How severe is CVE-2026-73500?
CVE-2026-73500 is rated High with a CVSS score of 8.7. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-73500?
Yes. A fix has been recorded for CVE-2026-73500. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-73500 affect?
CVE-2026-73500 affects etcd prior to 3.5.33, etcd prior to 3.6.14, etcd prior to 3.7.1, Kubernetes control planes using affected etcd instances, and 1 further product or version. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-73500?
Upgrade to etcd 3.5.33/3.6.14/3.7.1 and restrict TLS listener access via firewall/ACLs.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Remote attacker can open many TCP connections without TLS handshake, causing unbounded goroutines/map growth, memory exhaustion and DoS of etcd and K8s control plane.
Immediate action required
- affected< 3.5.33
- affected>= 3.6.0 and < 3.6.14
- affected>= 3.7.0-alpha.0 and < 3.7.1
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.