Security readout for executives and security teams
Plain-English summary
CVE-2021-39459 describes authenticated remote code execution in REDAXO CMS 5.12.1. A logged-in CMS user with module access could run PHP code on the hosting system through a malicious module. The public record does not provide CVSS, a patch version, or a wider affected-version range.
Executive priority
Treat this as a focused high-priority review where REDAXO 5.12.1 is deployed. The business risk is full compromise of the web host by an authenticated CMS user, but the evidence does not show unauthenticated exploitation or confirmed active abuse.
Technical view
The issue is in the modules component of Yakamara Media REDAXO CMS 5.12.1. The CVE states an authenticated CMS user can execute code on the host via a module containing malicious PHP code. Supplied sources do not include CWE, CVSS vector, vendor advisory, or remediation details.
Likely exposure
Likely exposure is REDAXO CMS 5.12.1 installations where CMS users can create or edit modules. Risk is higher when administrative CMS accounts are shared, weakly protected, or granted to semi-trusted users.
Exploitation context
The CVE record supports authenticated code execution. It is not listed as KEV in the supplied bundle, and no cited source here confirms active exploitation in the wild. Public GitHub references exist, but exploit reliability and real-world use are not established by the bundle.
Researcher notes
The record is sparse: affected data is generic, severity is unknown, and no official fix is included in the supplied sources. Validate against live REDAXO deployments and vendor release notes. Avoid expanding scope beyond version 5.12.1 without additional evidence.
Mitigation direction
- Identify REDAXO CMS 5.12.1 deployments and module-editing users.
- Check REDAXO vendor guidance for fixed versions or supported remediation.
- Restrict module creation and editing to trusted administrators only.
- Review CMS accounts, remove stale users, and enforce strong authentication.
- Back up affected sites before applying vendor-supported updates.
Validation and detection
- Inventory REDAXO version numbers across public and internal sites.
- Confirm whether module editing is enabled for non-administrator users.
- Review CMS audit logs for unexpected module changes.
- Inspect hosting logs for suspicious PHP execution after module edits.
- Verify vendor remediation status before closing the finding.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
Execution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-39459 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/evildrummer/CVE-2021-XYZCVE reference · x_refsource_MISC
- https://github.com/evildrummer/MyOwnCVEs/tree/main/CVE-2021-39459CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.