Cyber Resilience

CVE-2021-4367

MediumPublic PoC

Published: 07 June 2023

Published
07 June 2023
Modified
08 April 2026
KEV Added
Patch
CVSS Score v3.1 6.4 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
EPSS Score 0.0026 49.1th percentile
Risk Priority 13 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-4367 is a medium-severity Cross-site Scripting (CWE-79) vulnerability in Flothemes Flo Forms. Its CVSS base score is 6.4 (Medium).

Operationally, ranked at the 49.1th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

The Flo Forms – Easy Drag & Drop Form Builder plugin for WordPress is vulnerable to Stored Cross-Site Scripting via Options Change by using the flo_import_forms_options AJAX action in versions up to, and including, 1.0.35 due to insufficient input sanitization…

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and output escaping along with missing capability checks. This makes it possible for authenticated attackers, like subscribers, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

flothemes
flo forms
≤ 1.0.35

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-79

Penetration testing submits XSS payloads to web applications, detecting cross-site scripting flaws for subsequent remediation.

addresses: CWE-79

Validates web inputs to reject script-related content that could produce XSS.

addresses: CWE-79

Output validation against expected content can reject or sanitize script content in generated web pages, reducing XSS exploitability.

References