CVE-2026-34381 — admidio

Summary

Admidio relies on adm_my_files/.htaccess to deny direct HTTP access to uploaded documents. The Docker image ships with AllowOverride None in the Apache configuration, which causes Apache to silently ignore all .htaccess files. As a result, any file uploaded to the documents module regardless of the role-based permissions configured in the UI, is directly accessible over HTTP without authentication by anyone who knows the file path. The file path is disclosed in the upload response JSON.

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Root Cause

File 1: Intended protection (ignored):
adm_my_files/.htaccess

Require all denied

<img width="408" height="403" alt="imagen" src="https://github.com/user-attachments/assets/95f0d389-a1a9-4dc4-9840-7f189d2c58ff" />

File 2: Apache config that neutralizes it:

• Command in order to search in Docker container: docker exec admidio-sec-app cat /etc/apache2/apache2.conf

/etc/apache2/apache2.conf (Docker image)

<Directory ${APACHE_DOCUMENT_ROOT}>
    AllowOverride None
</Directory>

<img width="492" height="328" alt="imagen" src="https://github.com/user-attachments/assets/2f2e09b1-0c2e-4932-8698-a40f6b92e917" />

AllowOverride None instructs Apache to skip .htaccess processing entirely, the deny rule never executes. The upload directory is inside the web root at /opt/app-root/src/adm_my_files/ and returns HTTP 200 for direct requests.

File 3: Upload response leaks the direct URL: system/file_upload.php, upload response JSON:

<img width="1528" height="624" alt="imagen" src="https://github.com/user-attachments/assets/50e66fde-ff41-4efa-adc9-ceeb5b23a97d" />

{
  "files": [{
    "name": "sensitive_poc.txt",
    "url": "http://TARGET/adm_my_files/documents_research/TEST-SENSITIVE/sensitive_poc.txt"
  }]
}

Verified PoC

Step 1: Admin creates a restricted folder (visible only to Administrator role):

modules/documents-files.php → permissions set to role Administrator only.

<img width="1161" height="784" alt="imagen" src="https://github.com/user-attachments/assets/25d81e44-9a7c-4991-b72e-6e664d176695" />

Step 2: Admin uploads a file to the restricted folder.

Upload response returns:

http://TARGET/adm_my_files/documents_research/TEST-SENSITIVE/sensitive_poc.txt

<img width="1239" height="294" alt="imagen" src="https://github.com/user-attachments/assets/84c1bcd1-47d7-4115-ac0f-653b0a6d7301" />

Step 3: Unauthenticated request retrieves the file:

curl -X GET 'http://TARGET/adm_my_files/documents_research/TEST-SENSITIVE/sensitive_poc.txt'
# Response: full file contents — no authentication required

<img width="1051" height="150" alt="imagen" src="https://github.com/user-attachments/assets/1ed7fab7-59cb-4d5b-8c60-12108490d1e4" />

Step 4: Confirm folder is role-restricted:

SELECT fil_name, fol_name, fol_public FROM adm_files JOIN adm_folders ON fil_fol_id = fol_id 
ORDER BY fil_id DESC LIMIT 5; -- fol_public = 0, role restricted — yet file is publicly accessible

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Impact

• Any document uploaded to Admidio including files restricted to specific roles is publicly accessible via direct HTTP request with no authentication required
• Role-based access control on the documents module is completely bypassed at the filesystem level
• Sensitive organizational documents (contracts, member data, financial records) are exposed to anyone who can guess or construct the file path
• The upload API response discloses the direct URL to the uploader, making path enumeration trivial

Recommended Fix

Option 1 (preferred): Enable AllowOverride in Apache config:

<Directory /opt/app-root/src/adm_my_files>
    AllowOverride All
</Directory>

Option 2: Move uploads outside the web root:
Store uploaded files in a directory outside DOCUMENT_ROOT and serve them exclusively through Admidio's download handler (modules/documents-files.php?mode=download), which enforces role checks before serving the file.

Option 3: Apache-level explicit deny (does not require .htaccess):

<Directory /opt/app-root/src/adm_my_files>
    Require all denied
</Directory>

The most robust long-term fix is Option 2 — moving uploads outside the web root eliminates the dependency on Apache configuration correctness entirely.

Reported by: Juan Felipe Oz @JF0x0r

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