Samba: group policy certificate enrollment uses http:// without validation
Summary
| CVE | CVE-2026-3012 |
|---|---|
| State | PUBLISHED |
| Assigner | redhat |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-05-27 11:16:18 UTC |
| Updated | 2026-05-27 14:54:20 UTC |
| Description | A flaw was found in Samba’s certificate auto-enrollment Group Policy handling. When certificate auto-enrollment is enabled, Samba may retrieve a CA certificate over an unencrypted HTTP connection and install it into the local trust store without proper verification. An attacker with the ability to intercept or redirect network traffic could exploit this behavior to supply a malicious certificate authority certificate, potentially allowing interception or spoofing of trusted communications. |
Risk And Classification
Primary CVSS: v3.1 8 HIGH from [email protected]
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N
EPSS: 0.000040000 probability, percentile 0.001810000 (date 2026-05-31)
Problem Types: CWE-345 | CWE-345 Insufficient Verification of Data Authenticity
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | [email protected] | Secondary | 8 | HIGH | CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N |
| 3.1 | CNA | CVSS | 8 | HIGH | CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N |
CVSS v3.1 Breakdown
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Red Hat | Red Hat Enterprise Linux 10 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 6 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 6 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 7 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 8 | Not specified | Not specified |
| CNA | Red Hat | Red Hat Enterprise Linux 9 | Not specified | Not specified |
| CNA | Red Hat | Red Hat OpenShift Container Platform 4 | Not specified | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| access.redhat.com/security/cve/CVE-2026-3012 | [email protected] | access.redhat.com | |
| bugzilla.samba.org/show_bug.cgi | [email protected] | bugzilla.samba.org | |
| bugzilla.redhat.com/show_bug.cgi | [email protected] | bugzilla.redhat.com | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
Vendor Comments And Credit
Discovery Credit
CNA: Red Hat would like to thank Arad Inbar (DREAM Security Research Team), Ben Grinberg (DREAM Security Research Team), Michalis Vasileiadis, and Nir Somech (DREAM Security Research Team) for reporting this issue. (en)
Additional Advisory Data
| Source | Time | Event |
|---|---|---|
| CNA | 2026-03-13T12:55:02.623Z | Reported to Red Hat. |
| CNA | 2026-05-27T09:17:49.862Z | Made public. |
Workarounds
CNA: Systems are not affected unless Samba Group Policy processing and certificate auto-enrollment are explicitly enabled. Administrators can reduce exposure by: Avoiding unnecessary use of certificate auto-enrollment. Ensuring your "smb.conf" does not contain a line like ```apply group policies = yes```. If , group policy is not be enabled, the vulnerable code will not run. Intercepting the HTTP request requires some control over the local network or other devices to intercept or redirect traffic. Some network administrators might assess this as a low risk on their networks.