Summary
etcd: tlsListener.acceptLoop spawns unbounded handshake goroutines with no deadline
Workarounds
Is there a way for users to fix or remediate the vulnerability without upgrading?
If upgrading is not immediately possible, then restrict network access. Limit which hosts can reach etcd's client (gRPC) port via firewall rules or network policy, reducing who can attempt exploitation.
Reporter
VMware By Broadcom
Impact
What kind of vulnerability is it? Who is impacted?
A network attacker who can reach an etcd TLS listener can open many TCP connections and never send a ClientHello. Each connection spawns a goroutine in the etcd server process that blocks indefinitely inside tls.Conn.Handshake(), and each is tracked in the pending map. Unbounded goroutine and map growth exhausts memory in the etcd process, causing loss of availability for the etcd cluster (and, when etcd backs Kubernetes, the control plane).
The application allocates resources such as memory, threads, or file descriptors based on untrusted input without enforcing a cap. Typical impact: resource exhaustion leading to denial of service.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Has the problem been patched? What versions should users upgrade to?
This vulnerability is patched in the following versions:
- etcd 3.7.1
- etcd 3.6.14
- etcd 3.5.33
Frequently Asked Questions
- What is GHSA-6VCH-Q96H-7GC3? GHSA-6VCH-Q96H-7GC3 is a high-severity allocation of resources without limits or throttling vulnerability in go.etcd.io/etcd/v3 (go), affecting versions >= 3.7.0-alpha.0, < 3.7.1. It is fixed in 3.7.1, 3.6.14, 3.5.33. The application allocates resources such as memory, threads, or file descriptors based on untrusted input without enforcing a cap.
- Which versions of go.etcd.io/etcd/v3 are affected by GHSA-6VCH-Q96H-7GC3? go.etcd.io/etcd/v3 (go) versions >= 3.7.0-alpha.0, < 3.7.1 is affected.
- Is there a fix for GHSA-6VCH-Q96H-7GC3? Yes. GHSA-6VCH-Q96H-7GC3 is fixed in 3.7.1, 3.6.14, 3.5.33. Upgrade to this version or later.
- Is GHSA-6VCH-Q96H-7GC3 exploitable, and should I be worried? Whether GHSA-6VCH-Q96H-7GC3 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether GHSA-6VCH-Q96H-7GC3 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix GHSA-6VCH-Q96H-7GC3?
- Upgrade
go.etcd.io/etcd/v3to 3.7.1 or later - Upgrade
go.etcd.io/etcd/v3to 3.6.14 or later - Upgrade
go.etcd.io/etcd/v3to 3.5.33 or later
- Upgrade