CVE-2020-9281Public exploitNetwork attack vector

Script execution via externally supplied protected comments

Published Mar 7, 2020 · Updated Aug 4, 2024

Cross-site scripting in CKEditor HTML Data Processor before 4.14.0 allows remote attackers to run script via a crafted protected comment. The processor accepts an externally supplied cke_protected marker as internal protected content, causing embedded executable markup to remain unencoded. Exploitation requires a victim to paste the crafted HTML in WYSIWYG mode or source mode and return to WYSIWYG mode, which executes the script in the editor context.

CVSS severity6.1
Medium
EPSS probability4.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Cross-site scripting in CKEditor HTML Data Processor before 4.14.0 allows remote attackers to run script via a crafted protected comment. The processor accepts an externally supplied cke_protected marker as internal protected content, causing embedded executable markup to remain unencoded. Exploitation requires a victim to paste the crafted HTML in WYSIWYG mode or source mode and return to WYSIWYG mode, which executes the script in the editor context.

The record

CVE
CVE-2020-9281
Published
Mar 7, 2020
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 7, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.1GitHub Advisory DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/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.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

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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