5

CVE-2025-66406: smallstep certificates Incorrect Authorization

CVSS: 5.0v3.1MediumDeferred
AliasesCGA-f8j4-968w-vv37CGA-fj3f-76mc-hj23CGA-jjqq-hhqv-cjv5
Published 03-12-2025Last modified 03-12-2025
Open JSON

Vulnerability summary

CVE-2025-66406 is a medium (CVSS 5.0) Incorrect Authorization vulnerability in smallstep certificates. EPSS estimates a 0.15% chance of exploitation in the next 30 days, higher than 3.9% of scored vulnerabilities.

Overall risk
20/100
0100
Low · default modelHow is this calculated?
CVSS score
5.0/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.15%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 2 · Related 4
OPENSUSE-SU-2026:21483-1SUSE-SU-2025:4395-1CGA-PR93-635X-RQ27CGA-RH95-W3G3-PPH9

Timeline

  1. 03-12-2025
    PublishedVulnerability first disclosed.
  2. 03-12-2025
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

5 scores · 5 sources · 1 version

EPSS trend

Probability

0.15%

Chance of exploitation in the next 30 days

Percentile

4%

Versus all other CVEs

30-day change

0.00 pp

From 0.15% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.15%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Chainguard4 products
  • caddy< 2.10.2-r6
  • caddy-fips< 2.10.2-r6
  • caddy-man< 2.10.2-r6
  • caddy-src< 2.10.2-r6
Wolfi3 products
  • caddy< 2.10.2-r6
  • caddy-man< 2.10.2-r6
  • caddy-src< 2.10.2-r6
Github.com/smallstep1 product
  • certificates< 0.29.0
Smallstep1 product

4 vendors · 9 products

References

4 links