Step CA Has Authorization Bypass in ACME and SCEP Provisioners

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.