CVE-2026-34381

Admidio is an open-source user management solution. From version 5.0.0 to before version 5.0.8, 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. This issue has been patched in version 5.0.8.

Admidio is an open-source user management solution. From version 5.0.0 to before version 5.0.8, 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. This issue has been patched in version 5.0.8.

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.

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

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),…

Admidio is an open-source user management solution. From version 5.0.0 to before version 5.0.8, 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. This issue has been patched in version 5.0.8.

Admidio is an open-source user management solution. From version 5.0.0 to before version 5.0.8, 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. This issue has been patched in version 5.0.8.

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.

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

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),…