GHSA-h8cp-697h-8c8p
CRITICALGHSA-h8cp-697h-8c8p is a critical-severity (CVSS 10) Improper Authentication vulnerability in github.com/smallstep/certificates. O3 Security confirms whether GHSA-h8cp-697h-8c8p is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Step CA Has Authorization Bypass in ACME and SCEP Provisioners
Blast Radius
github.com/smallstep/certificatesReal-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
Summary
A security fix is now available for Step CA that resolves a vulnerability affecting deployments configured with ACME and/or SCEP provisioners.
All operators running these provisioners should upgrade to the latest release (v0.29.0) immediately.
The issue was discovered and disclosed by a research team during a security review. There is no evidence of active exploitation.
To limit exploitation risk during a coordinated disclosure window, we are withholding detailed technical information for now. A full write-up will be published in several weeks.
Embargo List
If your organization runs Step CA in production and would like advance, embargoed notification of future security updates, visit https://u.step.sm/disclosure to request inclusion on our embargo list.
Acknowledgements
This issue was identified and reported by Stephen Kubik of the Cisco Advanced Security Initiatives Group (ASIG)
Stay safe, and thank you for helping us keep the ecosystem secure.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐹Go | github.com/smallstep/certificates | all versions | 0.29.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/smallstep/certificates. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/smallstep/certificates to 0.29.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-h8cp-697h-8c8p 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 pinpoints whether GHSA-h8cp-697h-8c8p is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to GHSA-h8cp-697h-8c8p. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is GHSA-h8cp-697h-8c8p in your dependencies?
O3 detects GHSA-h8cp-697h-8c8p across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.