What is CVE-2026-30836?

CVE-2026-30836 is a critical-severity vulnerability in Smallstep Certificates, classified under Improper Authentication. CVSS score: 10.0/10. Published 2026-03-19.

How severe is CVE-2026-30836?

Critical severity. CVSS v3 base score is 10.0 out of 10.

Auth bypass in Smallstep Certificates

CVE-2026-30836

Step CA is an online certificate authority for secure, automated certificate management for DevOps. Versions 0.30.0-rc6 and below do not safeguard against unauthenticated certificate issuance through the SCEP UpdateReq. This issue has been fixed in version 0.30.0.

Vulnerability class: Broken Authentication

Published 2026-03-19 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 10.0 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N.

EPSS exploit prediction

EPSS: 0.003 (21.3th percentile), scored 2026-10-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 21st percentile — 21.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: +0.000

Affected products

Smallstep Certificates — versions < 0.30.0
Smallstep Step-Ca — versions 0.30.0

Weakness classification (CWE)

References

github.com/smallstep/certificates/security/advisories/GHSA-q4r8-xm5f-56gw (Vendor Advisory)
github.com/smallstep/certificates/commit/e6da031d5125cfd99fe9a26f74bb41e4dacca4… (Patch)
github.com/smallstep/certificates/releases/tag/v0.30.0-rc7 (Release Notes)

Frequently asked questions

What is CVE-2026-30836?: CVE-2026-30836 is a critical-severity vulnerability in Smallstep Certificates, classified under Improper Authentication. CVSS score: 10.0/10. Published 2026-03-19.
How severe is CVE-2026-30836?: Critical severity. CVSS v3 base score is 10.0 out of 10.