Security readout for executives and security teams
Plain-English summary
Monstra CMS 3.0.4 is reported to allow unrestricted file uploads because PHP extension filtering does not handle case variations. For a business, the concern is that a website using this CMS may accept files it should block. Severity is not scored in the provided sources, so urgency depends on whether Monstra 3.0.4 is deployed and upload functionality is exposed.
Executive priority
Prioritize discovery first. If Monstra 3.0.4 is present on a public site with uploads enabled, treat remediation as urgent because unrestricted upload flaws can affect site integrity. If not deployed, record as not applicable.
Technical view
The CVE describes a case-sensitive filtering weakness in Monstra 3.0.4 where PHP filename extension case is not properly filtered, resulting in unrestricted file upload. The provided record lists no CVSS score, CWE, confirmed affected CPEs, patch version, or official mitigation beyond the GitHub issue reference.
Likely exposure
Known exposure is limited to Monstra CMS 3.0.4 in the provided sources. Risk is most relevant where file upload functionality is reachable. The source bundle does not establish whether exploitation requires authentication, specific roles, or a particular server configuration.
Exploitation context
The source bundle does not show CISA KEV listing or confirmed active exploitation. It also does not provide exploit prevalence, public exploit maturity, or incident evidence. Treat this as a potential web application upload risk until deployment-specific exposure is validated.
Researcher notes
Evidence is sparse: the CVE description and referenced GitHub issue identify the weakness, but the provided metadata lacks scoring, CWE mapping, CPEs, exploit confirmation, and patch details. Avoid assuming affected versions beyond Monstra 3.0.4 without additional vendor evidence.
Mitigation direction
- Inventory internet-facing and internal sites for Monstra CMS 3.0.4.
- Check the Monstra project issue and vendor guidance for fixed versions or recommended actions.
- Restrict access to upload functionality while remediation guidance is confirmed.
- Review web server handling of uploaded files to prevent unintended script execution.
- Monitor upload locations for unexpected script-like files or suspicious changes.
Validation and detection
- Confirm whether any production or staging site runs Monstra CMS 3.0.4.
- Identify whether file upload features are enabled and reachable.
- Review application logs for suspicious upload activity around public web paths.
- Compare local code or configuration against the referenced GitHub issue details.
- Document authentication, role, and network prerequisites found during validation.
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.
File access behavior lookup
The CVE wording references file access or upload behavior, so file telemetry and web shell review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-40940 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/monstra-cms/monstra/issues/471CVE 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.