Arbitrary file upload via first-file-only validation
Published Sep 4, 2026 · Updated Sep 4, 2026
Unrestricted file upload in StellarWP LearnDash LMS 5.1.5 and earlier allows remote authenticated users to store disallowed files. The learndash_fileupload_process function iterates over a submitted file array but validates only its first element, so later PHP files reach the assignments upload directory. Exploitation requires subscriber-level access, course enrollment, and enabled assignment uploads; code execution additionally requires a non-default server configuration that executes uploaded files.
Summary
What happened
Unrestricted file upload in StellarWP LearnDash LMS 5.1.5 and earlier allows remote authenticated users to store disallowed files. The learndash_fileupload_process function iterates over a submitted file array but validates only its first element, so later PHP files reach the assignments upload directory. Exploitation requires subscriber-level access, course enrollment, and enabled assignment uploads; code execution additionally requires a non-default server configuration that executes uploaded files.
The record
- CVE
- CVE-2026-12483
- Published
- Sep 4, 2026
- Updated
- Sep 4, 2026
- Vendor
- Liquid Web
- Product
- LearnDash LMS
- Classifications
- CWE-434, T1105
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Sep 4, 2026CVE publishedPublication date reported by the CVE source.
- Sep 4, 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 <=5.1.5
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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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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