Security readout for executives and security teams
Plain-English summary
This vulnerability affects the WordPress Flo Forms plugin up to version 1.0.35. A logged-in low-privilege user, such as a subscriber, could store malicious script through plugin options. That script could later run for visitors or administrators who view affected pages, creating account, content-trust, and session-risk exposure.
Executive priority
Treat as a near-term remediation item, not an emergency unless the site allows untrusted logins. The main business risk is stored script execution against users or administrators, which can damage trust and support follow-on compromise.
Technical view
CVE-2021-4367 is stored XSS in Flo Forms via the flo_import_forms_options AJAX action. Sources cite insufficient sanitization, insufficient output escaping, and missing capability checks. The CVSS 3.1 score is 6.4, with low attack complexity, low privileges required, no user interaction required by the attacker, changed scope, and low confidentiality/integrity impact.
Likely exposure
Exposure is limited to WordPress sites running Flo Forms up to and including 1.0.35, especially where subscriber or other untrusted authenticated accounts exist. Public user registration increases practical risk.
Exploitation context
The source bundle does not show CISA KEV listing or confirmed active exploitation. Nintechnet describes a zero-day vulnerability being fixed, but the provided evidence does not establish current exploitation in the wild.
Researcher notes
Evidence supports stored XSS through options change with missing authorization controls. Sources do not provide exploit telemetry in this bundle, and fixed-version detail is incomplete here. Validate against authoritative plugin or vulnerability database records before closing remediation.
Mitigation direction
- Identify any WordPress sites using Flo Forms version 1.0.35 or earlier.
- Check vendor, Wordfence, WPScan, or plugin guidance for the confirmed fixed release.
- Update to a confirmed patched version, or disable/remove the plugin if unsupported.
- Restrict subscriber registration and remove unnecessary low-privilege accounts.
- Review stored form options and pages for unexpected script content.
Validation and detection
- Inventory installed WordPress plugins and record Flo Forms versions.
- Confirm whether subscriber-level users exist or public registration is enabled.
- Review logs for authenticated requests involving flo_import_forms_options.
- Inspect affected pages and plugin options for unexpected stored scripts.
- Verify remediation against Wordfence, WPScan, and vendor-published guidance.
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-79: User-session and phishing behavior lookup
Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. 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-2021-4367 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
- 6.4 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/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:C/C:L/I:L/A:N3.12.7Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
6.4MediumVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://www.wordfence.com/threat-intel/vulnerabilities/id/a175e103-ab89-404b-8736-94d0d93d6cf3?source=cveCVE reference
- https://blog.nintechnet.com/zero-day-vulnerability-fixed-in-wordpress-flo-forms-plugin/CVE reference
- https://wpscan.com/vulnerability/b4a83501-c727-4c9b-a9a1-46b399ab0caaCVE reference
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 Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.