CVE-2021-4227Public exploitNetwork attack vector

Arbitrary content loading via unsanitized Source comments

Published Jan 16, 2024 · Updated Jun 2, 2025

Stored iframe injection in antoniobg ARK WYSIWYG Comment Editor 2.15.6 and earlier allows remote attackers to load arbitrary web content. The Source editor submits comment HTML to WordPress without properly sanitizing or encoding iframe markup before the comment is rendered. An unauthenticated commenter can place an external iframe in a comment, but moderation must approve the comment before embedded content loads when approval is required.

CVSS severity5.3
Medium
EPSS probability0.61%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored iframe injection in antoniobg ARK WYSIWYG Comment Editor 2.15.6 and earlier allows remote attackers to load arbitrary web content. The Source editor submits comment HTML to WordPress without properly sanitizing or encoding iframe markup before the comment is rendered. An unauthenticated commenter can place an external iframe in a comment, but moderation must approve the comment before embedded content loads when approval is required.

The record

CVE
CVE-2021-4227
Published
Jan 16, 2024
Updated
Jun 2, 2025
Vendor
antoniobg
Product
ARK WYSIWYG Comment Editor
Classifications
CWE-74, CWE-80
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 16, 2024CVE publishedPublication date reported by the CVE source.
  2. Jun 2, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=2.15.6

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

antoniobg · ARK WYSIWYG Comment Editorversion=0 <=2.15.6

Published CVSS scores

5.3CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-74Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')
CWE-80Improper Neutralization of Script-Related HTML Tags in a Web Page (Basic XSS)

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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