Security readout for executives and security teams
Plain-English summary
CVE-2026-28133 affects the WordPress Filr plugin from WP Chill through version 1.2.14. A low-privileged user may be able to upload a dangerous file type, including a web shell, potentially leading to full site compromise. Public sources do not show known active exploitation or a confirmed patched version in the provided data.
Executive priority
Prioritize review within the current remediation cycle for any public WordPress site using Filr. Escalate faster if the site has untrusted logged-in users or handles sensitive data. Treat as high business risk because successful exploitation could enable site takeover.
Technical view
The issue is CWE-434: unrestricted upload of a file with dangerous type in package filr-protection. CVSS is 8.5 high: network-accessible, low privileges required, no user interaction, high impact to confidentiality, integrity, and availability, with high attack complexity. The CVE description names versions through 1.2.14; the Patchstack URL title references 1.2.12, so version data should be verified.
Likely exposure
WordPress sites running the WP Chill Filr plugin, especially versions up to 1.2.14, are potentially exposed. Because the vector requires low privileges, sites allowing subscriber, customer, contributor, or other untrusted authenticated access may face higher practical risk.
Exploitation context
The vulnerability could allow upload of a web shell to the web server. No CISA KEV listing is present in the provided bundle, and no cited source states active exploitation. Attack complexity is rated high, so exploitation may depend on configuration or workflow conditions not detailed here.
Researcher notes
Provided metadata is limited and contains version ambiguity: CVE text says through 1.2.14, while the Patchstack URL references 1.2.12. The affected array also appears incomplete. Do not assume exploit availability, fixed versions, or exact reachable endpoints without vendor or Patchstack confirmation.
Mitigation direction
- Check WP Chill and Patchstack guidance for a patched Filr version or official workaround.
- Upgrade Filr if the vendor identifies a fixed release.
- Disable or remove Filr if no safe fixed version is available and exposure is unacceptable.
- Limit untrusted user accounts until remediation is confirmed.
- Review upload handling and server execution restrictions for WordPress uploads.
Validation and detection
- Inventory WordPress sites for the Filr plugin.
- Confirm installed Filr versions and compare against <= 1.2.14.
- Identify whether untrusted authenticated users can access Filr upload features.
- Review web server logs for suspicious upload activity.
- Check file storage locations for unexpected executable files.
- Monitor vendor and Patchstack pages for corrected version details.
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-434: File access and web shell behavior lookup
File traversal and upload weaknesses can lead teams to review file, web shell, execution, and collection telemetry. 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 lookupFile 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-2026-28133 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
- High
- CVSS
- 8.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
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:H/PR:L/UI:N/S:C/C:H/I:H/A:H1.86Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
8.5HighVector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
Source materials
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.
Unrestricted Upload of File with Dangerous Type
Unrestricted Upload of File with Dangerous Type represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.