Security readout for executives and security teams
Plain-English summary
CVE-2021-26031 affects Joomla! CMS versions 3.0.0 through 3.9.25. Weak filtering around module layout settings could allow local file inclusion. For executives, the main concern is public Joomla sites that may expose sensitive local files if left on vulnerable versions.
Executive priority
Prioritize remediation for public Joomla sites in the affected range. The severity is not scored in the supplied sources, but LFI can create meaningful data exposure risk.
Technical view
The issue is an LFI risk in Joomla! Core caused by inadequate filtering of module layout settings. The provided sources identify affected versions as Joomla! 3.0.0 through 3.9.25. No CVSS score, CWE, exploit details, or fixed version is provided in the bundle.
Likely exposure
Exposure is most likely on internet-facing Joomla! CMS deployments running versions 3.0.0 through 3.9.25, especially sites with modules using configurable layout settings.
Exploitation context
The source bundle does not show CISA KEV listing and provides no cited evidence of active exploitation. Treat exploitation status as unconfirmed rather than absent.
Researcher notes
Evidence is limited to the CVE record and Joomla advisory metadata. Do not assume exploitability conditions, authentication requirements, or fixed versions beyond the affected range without reviewing the vendor advisory directly.
Mitigation direction
- Inventory Joomla! sites and identify any running versions 3.0.0 through 3.9.25.
- Review the Joomla! vendor advisory for the corrected release and upgrade guidance.
- Apply vendor-supported updates through normal change control.
- Restrict administrative access and review module configuration permissions where feasible.
- Monitor Joomla! security channels for any later exploitation or remediation updates.
Validation and detection
- Confirm Joomla! core versions across production, staging, and backup environments.
- Check whether affected module layout settings are available to untrusted or lower-privileged users.
- Review web server and application logs for suspicious local file path references.
- Verify remediation by confirming the site is no longer in the affected version range.
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.
CVE-2021-26031 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://developer.joomla.org/security-centre/851-20210402-core-inadequate-filters-on-module-layout-settings.htmlCVE reference · x_refsource_MISC, vendor-advisory
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.