CVE-2023-0491Public exploitNetwork attack vector

Stored XSS via unescaped shortcode attributes

Published Mar 27, 2023 · Updated Feb 19, 2025

Stored cross-site scripting in Schedulicity WordPress plugin through 2.21 allows remote authenticated users to run script via shortcode attributes. The schedule_now_button shortcode places the bizkey attribute into page output without validation or escaping, so crafted attribute text becomes executable markup. Contributor access is required to embed the shortcode, and execution occurs when another user views or interacts with the stored page.

CVSS severity6.5
Medium
EPSS probability0.56%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Stored cross-site scripting in Schedulicity WordPress plugin through 2.21 allows remote authenticated users to run script via shortcode attributes. The schedule_now_button shortcode places the bizkey attribute into page output without validation or escaping, so crafted attribute text becomes executable markup. Contributor access is required to embed the shortcode, and execution occurs when another user views or interacts with the stored page.

The record

CVE
CVE-2023-0491
Published
Mar 27, 2023
Updated
Feb 19, 2025
Vendor
Schedulicity
Product
Schedulicity
Classifications
CWE-79, T1059.007
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Mar 27, 2023CVE publishedPublication date reported by the CVE source.
  2. Feb 19, 2025Record 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 <=2.21

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Schedulicity · Schedulicityversion=0 <=2.21

Published CVSS scores

6.5CISA ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1059.007JavaScript/JScript

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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