CVE-2026-115732
Description
Incorrect authorization in the certificate-name matching of trapperkeeper-authorization, as used by Puppet Server, allows a client that holds a CA-signed certificate whose name extends or shortens an authorized hostname to be authorized as that host. This enables impersonation of other nodes and, in Puppet Enterprise, access to certificate-authority administration and remote command execution on managed nodes. Exploitation requires a certificate with a colliding name, which the certificate authority issues by approval or autosign.
Mitigation
Until patched, avoid autosigning certificate requests without strong verification, and do not approve CSRs for names that are suffixes/prefixes of existing authorized certnames.
--- CME Mitigation Guidance (2026-11-04) ---
Disclaimer: The following mitigation solutions are provided as a courtesy, pending the application of an official patch. This content was generated utilizing AI tools in conjunction with data from https://cmetaxonomy.org. Customers are advised to independently evaluate and test these temporary mitigations within their own infrastructure.
The highest-value action is to enforce exact domain segment length matching and full domain equality for certificate hostname ACL checks in trapperkeeper-authorization: upgrade to openvox-server and openvoxdb 9.2.0, 8.18.0 (or the fixed Puppetserver/Openvox Server builds), which require domain segment counts to match for non-wildcard rules or validate full domain equality during ACL evaluation, closing all 2 injection vectors (subdomain certificate acquisition via autosigning, prefix or suffix certificate signing via CA approval). Until patched, this is a concern on Puppet Server, OpenVox Server, and OpenVoxDB deployments, so Avoid autosigning certificate requests without strict verification, reject CSR approvals for names that extend or shorten authorized certnames, and restrict network access to server endpoints. As a compensating measure, Deploy EDR agents to detect anomalous post-exploitation activity and unauthorized command execution on nodes targeted through catalog impersonation, Configure Falco or eBPF runtime security to detect anomalous process executions and unexpected shells spawned following catalog-driven execution, and Integrate application admin event logging with SIEM to detect unauthorized CA administrative operations or node catalog downloads with mismatched certnames. These controls limit blast radius and contain exploitation, but they do not fix the underlying flawed hostname ACL matching defect — apply the upstream patch to fully remediate.
Highest-impact CME: CME-1001 EDR Agent (Endpoint Detection & Response) (medium)
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 9.9 | N/A | N/A |
| Attack Vector | Network | N/A | N/A |
| Attack Complexity | Low | N/A | N/A |
| Privileges Required | Low | N/A | N/A |
| User Interaction | None | N/A | N/A |
| Scope | Changed | N/A | N/A |
| Confidentiality | High | N/A | N/A |
| Integrity Impact | High | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
Red Hat CVSS v3 Score Explanation
Requires a CA-signed client certificate with a colliding hostname (often via autosign). Successful impersonation can expose catalogs/secrets and, in PE, escalate to CA admin and agent command execution (Scope Changed).
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Application Data; Read Files or Directories
An attacker could bypass intended access restrictions to read sensitive data, either by reading the data directly from a data store that is not correctly restricted, or by accessing insufficiently-protected, privileged functionality to read the data.
Integrity
Technical Impact: Modify Application Data; Modify Files or Directories
An attacker could bypass intended access restrictions to modify sensitive data, either by writing the data directly to a data store that is not correctly restricted, or by accessing insufficiently-protected, privileged functionality to write the data.
Access Control
Technical Impact: Gain Privileges or Assume Identity; Bypass Protection Mechanism
An attacker could bypass intended access restrictions to gain privileges by modifying or reading critical data directly, or by accessing privileged functionality.
Confidentiality,Integrity,Availability
Technical Impact: Execute Unauthorized Code or Commands
An attacker could use elevated privileges to execute unauthorized commands or code.
Availability
Technical Impact: DoS: Crash, Exit, or Restart; DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)
An attacker could gain unauthorized access to resources on the system and excessively consume those resources, leading to a denial of service.
Acknowledgements
Upstream acknowledges Alain (Neodyme) as the original reporter.
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