GHSA-h6xx-pmxh-3wgp is a high-severity (CVSS 8.1) Improper Authentication vulnerability in go.etcd.io/etcd/v3. A fix is available for go.etcd.io/etcd/v3 — see the affected versions and patch details below.
go.etcd.io/etcd Authentication Bypass
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
GHSA-h6xx-pmxh-3wgp plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,166 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
go.etcd.io/etcd/v3🐹go.etcd.io/etcd/v3🐹go.etcd.io/etcdReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.
Description
etcd versions 3.2.x before 3.2.26 and 3.3.x before 3.3.11 are vulnerable to an improper authentication issue when role-based access control (RBAC) is used and client-cert-auth is enabled. If an etcd client server TLS certificate contains a Common Name (CN) which matches a valid RBAC username, a remote attacker may authenticate as that user with any valid (trusted) client certificate in a REST API request to the gRPC-gateway.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | go.etcd.io/etcd/v3 | ≥ 3.2.0&&< 3.2.26 | 3.2.26go get go.etcd.io/etcd/v3@v3.2.26 |
| 🐹Go | go.etcd.io/etcd/v3 | ≥ 3.3.0&&< 3.3.11 | 3.3.11go get go.etcd.io/etcd/v3@v3.3.11 |
| 🐹Go | go.etcd.io/etcd | all versions | 0.5.0-alpha.5.0.20190108173120-83c051b701d3go get go.etcd.io/etcd@v0.5.0-alpha.5.0.20190108173120-83c051b701d3 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for go.etcd.io/etcd/v3, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update go.etcd.io/etcd/v3 to 3.2.26 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-h6xx-pmxh-3wgp is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like GHSA-h6xx-pmxh-3wgp can be triaged on real exposure rather than presence alone.
Tailored to GHSA-h6xx-pmxh-3wgp. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
OpenShift Container Platform 3.x, and 4.1 versions do not use etcd Role-based access control so they are not affected.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Enterprise Linux 7 Extras | etcd-0:3.2.26-1.el7 | RHSA-2019:1352 |
Frequently Asked Questions
Is GHSA-h6xx-pmxh-3wgp in your dependencies?
O3 Security finds GHSA-h6xx-pmxh-3wgp across Go dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.