Security readout for executives and security teams
Plain-English summary
This WordPress plugin issue lets a low-privileged logged-in user see custom upload extensions configured by administrators. It is an information disclosure problem, not a takeover or data destruction issue based on the supplied sources.
Executive priority
Treat this as a medium-priority cleanup item. It is unlikely to justify emergency response alone, but it can expose internal upload policy details to low-privilege users.
Technical view
WP Upload Restriction 2.2.3 and prior lack proper access control in getSelectedMimeTypesByRole, allowing low-level authenticated users to view administrator-added custom extensions. CVSS is 4.3 with low confidentiality impact only.
Likely exposure
WordPress sites using WP Upload Restriction version 2.2.3 or earlier are potentially exposed, especially if they allow many subscriber, contributor, customer, or other low-privilege accounts.
Exploitation context
The source bundle does not show CISA KEV listing or evidence of active exploitation. Exploitation requires authenticated low-level access and appears limited to viewing configured custom extensions.
Researcher notes
The evidence supports CWE-284 missing access control with confidentiality impact only. The supplied sources do not name a patched version, exploit availability, or broader product impact.
Mitigation direction
- Inventory WordPress sites for WP Upload Restriction installations and versions.
- Check vendor or Wordfence guidance for a fixed version or replacement recommendation.
- Disable or remove the plugin where it is not business-critical.
- Limit low-privilege WordPress accounts to users with a real business need.
- Review upload policy exposure with site owners and administrators.
Validation and detection
- Confirm whether WP Upload Restriction is installed on each WordPress site.
- Record the plugin version and compare it with 2.2.3 and prior.
- Review user roles that can authenticate to affected sites.
- Check administrative configuration for sensitive custom extension rules.
- Document whether vendor guidance identifies a fixed release.
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.
CWE-284: Authorization and privilege behavior lookup
Authorization weaknesses can support privilege escalation and valid-account review, depending on exploit path. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2021-34627 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
- Medium
- CVSS
- 4.3 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
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 vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N2.81.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
4.3MediumVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://www.wordfence.com/vulnerability-advisories/#CVE-2021-34627CVE 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.
Improper Access Control
Improper Access Control represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.