CVE Intelligence
Medium Integrity

CVE-2026-3012 — Samba: group policy certificate enrollment uses http:// without validation

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.

Published May 27, 2026 · Updated Oct 15, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: redhat

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.2% (30-day exploitation probability)+2
  • Technical severity (medium)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.23%
ahead of 12% of scored CVEs · Oct 15, 2026
Affects
Red Hat
Enterprise Linux and 22 more
CVSS base
6.8
Medium · 5 source(s)
Prioritization reference: 8.0 provisional

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
None
none · proof-of-concept · active
Automatable
No
can an attacker script the kill-chain steps
Technical impact
Total
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Red Hat Enterprise Linux, Red Hat Openshift Container Platform, Red Hat Red Hat Enterprise Linux 10…).
  2. Apply the documented mitigations until a definitive fix is available.
  3. Search available logs for exploit probes matching the vulnerability class (integrity), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Red Hat Enterprise Linux version 9.0version 7.0 Vulnerable NIST National Vulnerability Database
Red Hat Openshift Container Platform version 4.0 Vulnerable NIST National Vulnerability Database
Red Hat Red Hat Enterprise Linux 10 versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Red Hat Red Hat Enterprise Linux 10.0 Extended Update Support versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Red Hat Red Hat Enterprise Linux 7 versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Red Hat Red Hat Enterprise Linux 8 versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Red Hat Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Red Hat Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Red Hat Red Hat Enterprise Linux 8.8 Telecommunications Update Service versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Red Hat Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Red Hat Red Hat Enterprise Linux 9 versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Red Hat Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Red Hat Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Red Hat Red Hat Enterprise Linux 9.6 Extended Update Support versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Red Hat Red Hat OpenShift Container Platform 4.12 versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Red Hat Red Hat OpenShift Container Platform 4.13 versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Red Hat Red Hat OpenShift Container Platform 4.14 versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Red Hat Red Hat OpenShift Container Platform 4.15 versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Red Hat Red Hat OpenShift Container Platform 4.16 versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Red Hat Red Hat OpenShift Container Platform 4.17 versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Red Hat Red Hat OpenShift Container Platform 4.18 versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Red Hat Red Hat OpenShift Container Platform 4.19 versions not specified by the source Vulnerable CVE Program (cve.org) e CISA ADP
Samba Samba ≥ 4.16.0 and < 4.21.0 Vulnerable NIST National Vulnerability Database

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Adjacent
Attack complexity
High
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
8.0 CVSS 3.1 High 1.6 5.8 secalert@redhat.com via NIST National Vulnerability Database
8.0 CVSS 3.1 High 1.6 5.8 0b0ca135-0b70-47e7-9f44-1890c2a1c46c via NIST National Vulnerability Database
8.0 CVSS 3.1 High — — GitHub, Inc. via GitHub Security Advisories
8.0 CVSS 3.1 High — — redhat via CVE Program (cve.org) e CISA ADP
6.8 CVSS 3.1 Medium 1.6 5.2 nvd@nist.gov via NIST National Vulnerability Database
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N (score shown at the top: nvd@nist.gov)
Scoring entities (NIST, CNA, ADP) score independently; each score is shown with its origin. For prioritization we use 8.0 (secalert@redhat.com via NIST National Vulnerability Database) as a conservative provisional reference — not a definitive official score.

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-345 · Insufficient Verification of Data Authenticity

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 15, 2026 · 3 reading(s) · max 0.23%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Not enough vector or weakness data: use the affected application’s logs as a starting point.
application logs

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · red hat/red hat enterprise linux 10, red hat/red hat enterprise linux 10.0 extended update support, red hat/red hat ente
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 13, 2026
  • Fix documented
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVSS changed · 6.8
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Modified
    Oct 13, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVE published
    May 27, 2026 · redhat

Source activity

Repeated readings are counted rather than listed.

  • 2× References added · Oct 15, 2026 – Oct 15, 2026
  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

30 on the record

Elsewhere on this site

Red Hat
every CVE for this vendor
Integrity
same class
CWE-345
other pages naming this weakness

Related CVEs (same products)

  • Medium CVE-2026-110927 Openssh: openssh: a compressed payload can expand past the maximum packet size 5h
  • Medium CVE-2026-110924 Openssh: openssh: gssapi delegated credentials can be stored after a failed authentication 5h
  • Medium CVE-2026-110926 Openssh: openssh: shared lz77 compression dictionary leaks plaintext across channels 13h
  • Medium CVE-2026-110925 Openssh: openssh: '$' and '\' in a command-line username expand through %u 13h
  • Medium CVE-2026-110923 Openssh: openssh: sftp can write outside the destination directory from a server-supplied path 13h
  • Medium CVE-2026-86849 Dpdk: dpdk: integer overflow combined with missing validation leads to host buffer overflow in vhost-crypto 1d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-3012 is "Samba: group policy certificate enrollment uses http:// without validation", rated Medium. It affects Enterprise Linux (Red Hat); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 6.8 describes technical severity. EPSS 0.23% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

Comments

Moderated technical discussion. Read the community guidelines.

No comments yet.

Sign in or create an account to comment and suggest corrections.