Authenticated arbitrary file upload via missing type validation
Published Dec 5, 2025 · Updated Apr 8, 2026
Arbitrary file upload in ContentStudio 1.3.7 and earlier allows remote authenticated users with Author access to place files on the server. The cstu_update_post() function saves attacker-supplied uploads without validating file types, permitting dangerous extensions and embedded PHP. Author-level WordPress access is required, and a server configured to execute the uploaded file exposes code execution under the web server account.
Summary
What happened
Arbitrary file upload in ContentStudio 1.3.7 and earlier allows remote authenticated users with Author access to place files on the server. The cstu_update_post() function saves attacker-supplied uploads without validating file types, permitting dangerous extensions and embedded PHP. Author-level WordPress access is required, and a server configured to execute the uploaded file exposes code execution under the web server account.
The record
- CVE
- CVE-2025-12181
- Published
- Dec 5, 2025
- Updated
- Apr 8, 2026
- Vendor
- ContentStudio
- Product
- ContentStudio
- Classifications
- CWE-434, T1505.003
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Dec 5, 2025CVE publishedPublication date reported by the CVE source.
- Apr 8, 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 <=1.3.7
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
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
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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