Contributor-level stored XSS via unsanitized size attribute
Published Aug 28, 2026 · Updated Aug 28, 2026
Stored XSS in ThemeFusion Avada Builder 3.15.6 and earlier allows remote authenticated users to inject scripts through the size shortcode attribute. The save path applies wp_kses_post to an attribute-only payload containing no angle brackets, then renders the insufficiently escaped size value into page output. Contributor-level access is required to store the payload, which executes in the browser whenever a user visits the injected page.
Summary
What happened
Stored XSS in ThemeFusion Avada Builder 3.15.6 and earlier allows remote authenticated users to inject scripts through the size shortcode attribute. The save path applies wp_kses_post to an attribute-only payload containing no angle brackets, then renders the insufficiently escaped size value into page output. Contributor-level access is required to store the payload, which executes in the browser whenever a user visits the injected page.
The record
- CVE
- CVE-2026-16654
- Published
- Aug 28, 2026
- Updated
- Aug 28, 2026
- Vendor
- ThemeFusion
- Product
- Avada Builder
- Classifications
- T1059.007
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 28, 2026CVE publishedPublication date reported by the CVE source.
- Aug 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.
- Affected versionversion=0 <=3.15.6
What conditions does exploitation require?
What is affected?
Published CVSS scores
No CVSS assessment is available in this record.
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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