Improper Authorization Check for SSH Certificate Revocation
Priority LOW 22CWE-863Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- High
- User interaction
- None
- Attack complexity
- High
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- None · Low · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-863.
Summary
Step CA is an online certificate authority for secure, automated certificate management for DevOps. Prior to 0.29.0, there is an improper authorization check for SSH certificate revocation. This affects deployments configured with the SSHPOP provisioner. This vulnerability is fixed in 0.29.0.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00162 5th percentileScored 2026-11-07
Fix Fixed certificates (smallstep): 0.29.0github.com/smallstep/certificates (Go): 0.29.0
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
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 0.29.0 | 0.29.0 | Patch available | CNA |
| — | github.com/smallstep/certificates (Go) | before 0.29.0 | 0.29.0 | Patch available | GHSA-j7c9-79x7-8hpr |
- certificates Vendorsmallstep Affected before 0.29.0 Fixed in 0.29.0 Patch available CNA
- github.com/smallstep/certificates (Go) Vendor— Affected before 0.29.0 Fixed in 0.29.0 Patch available GHSA-j7c9-79x7-8hpr
Remediation
- Fix · CNA certificates (smallstep) Fixed in 0.29.0
- Fix · GHSA-j7c9-79x7-8hpr github.com/smallstep/certificates (Go) Fixed in 0.29.0 Advisory →
Vendor assessments
Timeline
- 2026-10-02 Threatist record created from CVE-2025-66406
- 2026-10-03 Alias added: GHSA-j7c9-79x7-8hpr
References
More smallstep vulnerabilities
- TI-2025-28554 Improper authentication in smallstep Step-CA CVSS 3.1CRITICAL 10.0
- TI-2026-23665 Step CA: Unauthenticated Certificate Issuance via SCEP UpdateReq (MessageType=18) CVSS 3.1CRITICAL 10.0
- 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-2025-66406 · CVE Program
- CVE-2025-66406 · NVD
- FIRST EPSS
- GHSA-j7c9-79x7-8hpr · GitHub Advisory Database · CC BY 4.0
- CVE-2025-66406 · 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