Step CA: Unauthenticated Certificate Issuance via SCEP UpdateReq (MessageType=18)
Priority MEDIUM 49CWE-287Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Security bypass, Spoofing
- Confidentiality · integrity · availability
- High · High · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-287 and CWE-295.
Summary
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.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00308 23rd percentileScored 2026-11-07
Fix Fixed certificates (smallstep): 0.30.0github.com/smallstep/certificates (Go): 0.30.0
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- Yes
- Technical impact
- Total
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| smallstep | certificates | before 0.30.0 | 0.30.0 | Patch available | CNA |
| — | github.com/smallstep/certificates (Go) | before 0.30.0 | 0.30.0 | Patch available | GHSA-q4r8-xm5f-56gw |
- certificates Vendorsmallstep Affected before 0.30.0 Fixed in 0.30.0 Patch available CNA
- github.com/smallstep/certificates (Go) Vendor— Affected before 0.30.0 Fixed in 0.30.0 Patch available GHSA-q4r8-xm5f-56gw
CPE configurations NVD · 7
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:smallstep:step-ca:*:*:*:*:*:go:*:* | before 0.30.0 | Vulnerable | smallstep |
| cpe:2.3:a:smallstep:step-ca:0.30.0:rc1:*:*:*:go:*:* | 0.30.0 rc1 | Vulnerable | smallstep |
| cpe:2.3:a:smallstep:step-ca:0.30.0:rc2:*:*:*:go:*:* | 0.30.0 rc2 | Vulnerable | smallstep |
| cpe:2.3:a:smallstep:step-ca:0.30.0:rc3:*:*:*:go:*:* | 0.30.0 rc3 | Vulnerable | smallstep |
| cpe:2.3:a:smallstep:step-ca:0.30.0:rc4:*:*:*:go:*:* | 0.30.0 rc4 | Vulnerable | smallstep |
| cpe:2.3:a:smallstep:step-ca:0.30.0:rc5:*:*:*:go:*:* | 0.30.0 rc5 | Vulnerable | smallstep |
| cpe:2.3:a:smallstep:step-ca:0.30.0:rc6:*:*:*:go:*:* | 0.30.0 rc6 | Vulnerable | smallstep |
- cpe:2.3:a:smallstep:step-ca:*:*:*:*:*:go:*:* Versions before 0.30.0 Vulnerable ·smallstep
- cpe:2.3:a:smallstep:step-ca:0.30.0:rc1:*:*:*:go:*:* Versions 0.30.0 rc1 Vulnerable ·smallstep
- cpe:2.3:a:smallstep:step-ca:0.30.0:rc2:*:*:*:go:*:* Versions 0.30.0 rc2 Vulnerable ·smallstep
- cpe:2.3:a:smallstep:step-ca:0.30.0:rc3:*:*:*:go:*:* Versions 0.30.0 rc3 Vulnerable ·smallstep
- cpe:2.3:a:smallstep:step-ca:0.30.0:rc4:*:*:*:go:*:* Versions 0.30.0 rc4 Vulnerable ·smallstep
- cpe:2.3:a:smallstep:step-ca:0.30.0:rc5:*:*:*:go:*:* Versions 0.30.0 rc5 Vulnerable ·smallstep
- cpe:2.3:a:smallstep:step-ca:0.30.0:rc6:*:*:*:go:*:* Versions 0.30.0 rc6 Vulnerable ·smallstep
Remediation
- Fix · CNA certificates (smallstep) Fixed in 0.30.0
- Fix · GHSA-q4r8-xm5f-56gw github.com/smallstep/certificates (Go) Fixed in 0.30.0 Advisory →
Vendor assessments
Timeline
- 2026-10-02 Threatist record created from CVE-2026-30836
- 2026-10-03 Alias added: GHSA-q4r8-xm5f-56gw
References
Advisory 2
More smallstep Step-ca vulnerabilities
- TI-2026-28924 Step CA affected by an index out of bounds panic in TPM attestation EKU validation CVSS 3.1LOW 3.7
Sources
- CVE-2026-30836 · CVE Program
- CVE-2026-30836 · NVD
- FIRST EPSS
- GHSA-q4r8-xm5f-56gw · GitHub Advisory Database · CC BY 4.0
- CVE-2026-30836 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences