CVE-2026-66705Public exploitNetwork attack vector

Unauthenticated browser script execution via dismiss control

Published Aug 6, 2026 · Updated Aug 6, 2026

Cross-site scripting in Facebook for WordPress 5.2.1 and earlier allows remote attackers to run script via a crafted data parameter. The admin-notice dismiss control in core/class-facebookwordpresssettingspage.php embeds user-controlled data into an inline onClick navigation value without context-appropriate escaping. No authentication is required to submit the value, but an administrator must open the affected settings page before the script runs in that browser session.

CVSS severity7.1
High
EPSS probability0.14%
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 Facebook for WordPress 5.2.1 and earlier allows remote attackers to run script via a crafted data parameter. The admin-notice dismiss control in core/class-facebookwordpresssettingspage.php embeds user-controlled data into an inline onClick navigation value without context-appropriate escaping. No authentication is required to submit the value, but an administrator must open the affected settings page before the script runs in that browser session.

The record

CVE
CVE-2026-66705
Published
Aug 6, 2026
Updated
Aug 6, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-79, CAPEC-591, T1189
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 6, 2026CVE publishedPublication date reported by the CVE source.
  2. Aug 6, 2026Record 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

7.1PatchstackCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L

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-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CAPEC-591Reflected XSS
T1189Drive-by Compromise

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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