CVE-2025-22261Network attack vector

Stored script execution via unneutralized shortcode input

Published Jan 7, 2025 · Updated Apr 28, 2026

Stored XSS in Marcus Sykes WP FullCalendar 1.5 and earlier allows remote authenticated users to execute scripts through a crafted shortcode. The shortcode path fails to neutralize Contributor-supplied input before that input is stored and rendered in a calendar page. Contributor access is required to store the payload, and another user's interaction with the affected page triggers execution in that visitor's browser.

CVSS severity6.5
Medium
EPSS probability0.29%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored XSS in Marcus Sykes WP FullCalendar 1.5 and earlier allows remote authenticated users to execute scripts through a crafted shortcode. The shortcode path fails to neutralize Contributor-supplied input before that input is stored and rendered in a calendar page. Contributor access is required to store the payload, and another user's interaction with the affected page triggers execution in that visitor's browser.

The record

CVE
CVE-2025-22261
Published
Jan 7, 2025
Updated
Apr 28, 2026
Vendor
Marcus Sykes
Product
WP FullCalendar
Classifications
CWE-79, CAPEC-592, T1059.007
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 7, 2025CVE publishedPublication date reported by the CVE source.
  2. Apr 28, 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?

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

  1. Affected versionversion=0 <=1.5 changes=[{"at":"1.6","status":"unaffected"}]

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Marcus Sykes · WP FullCalendarversion=0 <=1.5 changes=[{"at":"1.6","status":"unaffected"}]

Published CVSS scores

6.5PatchstackCVSS:3.1/AV:N/AC:L/PR:L/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CAPEC-592Stored XSS
T1059.007Command and Scripting Interpreter: JavaScript/JScript

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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