Authenticated post stylesheet modification via unchecked AJAX authorization
Published Jul 16, 2026 · Updated Jul 16, 2026
Authorization bypass in Themify Builder 7.7.7 and earlier allows remote authenticated users to overwrite or delete post CSS files. The tb_generate_on_fly AJAX handler generates or deletes CSS for a supplied post without verifying edit_post authorization. Subscriber access is sufficient because public front-end builder pages disclose the required tf_nonce; successful requests can alter private or draft post styling.
Summary
What happened
Authorization bypass in Themify Builder 7.7.7 and earlier allows remote authenticated users to overwrite or delete post CSS files. The tb_generate_on_fly AJAX handler generates or deletes CSS for a supplied post without verifying edit_post authorization. Subscriber access is sufficient because public front-end builder pages disclose the required tf_nonce; successful requests can alter private or draft post styling.
The record
- CVE
- CVE-2026-15407
- Published
- Jul 16, 2026
- Updated
- Jul 16, 2026
- Vendor
- Themify
- Product
- Themify Builder
- Classifications
- CWE-862, T1565.001
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jul 16, 2026CVE publishedPublication date reported by the CVE source.
- Jul 16, 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?
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- Affected versionversion=0 <=7.7.7
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
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Technologies
Your stack
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Your stack
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