Stored XSS via unescaped block CSS classes
Published Feb 6, 2023 · Updated Mar 25, 2025
Stored XSS in Ajay D'Souza Contextual Related Posts before 3.3.1 allows remote authenticated users to inject scripts through block options. The block renderer places the user-controlled Additional CSS Classes value into an HTML class attribute without validation or output escaping. Contributor access is required to save the block, and a visitor who hovers over the rendered block executes the stored script in the page context.
Summary
What happened
Stored XSS in Ajay D'Souza Contextual Related Posts before 3.3.1 allows remote authenticated users to inject scripts through block options. The block renderer places the user-controlled Additional CSS Classes value into an HTML class attribute without validation or output escaping. Contributor access is required to save the block, and a visitor who hovers over the rendered block executes the stored script in the page context.
The record
- CVE
- CVE-2023-0252
- Published
- Feb 6, 2023
- Updated
- Mar 25, 2025
- Vendor
- Ajay D'Souza
- Product
- Contextual Related Posts
- Classifications
- CWE-79, T1059.007
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Feb 6, 2023CVE publishedPublication date reported by the CVE source.
- Mar 25, 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.
- Affected versionversion=0 <3.3.1
What conditions does exploitation require?
What is affected?
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.
Weakness, pattern, technique
Public exploit references
- WPScan Additional CSS Classes proof of conceptproof of concept · validated
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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