Contributor media upload via omitted capability check
Published Aug 20, 2026 · Updated Aug 20, 2026
Authorization bypass in AI Agent by SiteGround before 1.2.8 allows remote authenticated users to upload media via the REST API. The /generate-content REST endpoint accepts an sg_ai_studio_gutenberg_nonce available to block-editor users but does not verify the upload_files capability before writing generated images into the WordPress media library. Contributor-level access or higher is enough because those users can obtain the nonce; the published impact is limited to unauthorized media-library writes.
Summary
What happened
Authorization bypass in AI Agent by SiteGround before 1.2.8 allows remote authenticated users to upload media via the REST API. The /generate-content REST endpoint accepts an sg_ai_studio_gutenberg_nonce available to block-editor users but does not verify the upload_files capability before writing generated images into the WordPress media library. Contributor-level access or higher is enough because those users can obtain the nonce; the published impact is limited to unauthorized media-library writes.
The record
- CVE
- CVE-2026-17153
- Published
- Aug 20, 2026
- Updated
- Aug 20, 2026
- Vendor
- SiteGround
- Product
- AI Agent by SiteGround
- Classifications
- CWE-862
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 20, 2026CVE publishedPublication date reported by the CVE source.
- Aug 20, 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 <=1.2.7
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What is affected?
Published CVSS scores
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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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