high CVSS 7.5

CVE-2026-34381·Docker vulnerability

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.

Severity
high
Software
Docker
Fixed in
5.0.8
Published
2026-03-31

Affected versions

From: 5.0.0

Until: 5.0.8

Fixed in: 5.0.8

How to fix this CVE

Upgrade Docker to the latest version that includes the patched Admidio image (5.0.8 or later). If running Admidio in Docker, ensure your Apache configuration explicitly sets AllowOverride All in the document root directory to allow .htaccess file restrictions to take effect. Verify that uploaded files are no longer directly accessible via HTTP without authentication after applying the fix.

sudo dnf update docker-ce

Defensia detects this vulnerability

What an exploitation attempt looks like

Sample log line indicative of exploitation attempts:

GET /adm_my_files/ HTTP/1.1" 200 (indicating successful retrieval of files that should be restricted by .htaccess); alternatively, log entries showing repeated requests to /adm_my_files/<filename> from non-authenticated sessions returning HTTP 200 responses

WAF mitigation (if patching is not yet possible)

Add this rule to your WAF to block exploitation attempts while you schedule the patch. 

Implement a WAF rule to block direct HTTP access to the /adm_my_files/ directory: deny requests matching `^/adm_my_files/.*` unless the user session contains a valid Admidio authentication token in cookies or headers.

How to check if you are affected

  1. Step 1: Check Docker version with `docker --version` and verify if Admidio is running in a container using `docker ps | grep admidio`
  2. Step 2: Inspect the running container's Apache configuration by executing `docker exec <container_id> grep -n 'AllowOverride' /etc/apache2/sites-enabled/*.conf` to confirm if AllowOverride is set to None
  3. Step 3: Test if the adm_my_files directory is accessible without authentication by attempting to fetch a known file path via curl: `curl -I http://<docker_host>/adm_my_files/<filename>` and verify if it returns 403 Forbidden or 200 OK
  4. Step 4: After upgrade, re-run the curl test from Step 3 and verify that .htaccess restrictions now block unauthenticated access, returning a 403 Forbidden response

FAQ

What is CVE-2026-34381?

This vulnerability affects Docker deployments of Admidio versions 5.0.0 through 5.0.7, where an Apache misconfiguration (AllowOverride None) causes .htaccess restrictions to be ignored, allowing unauthenticated HTTP access to uploaded documents via their disclosed file paths.

Is CVE-2026-34381 being actively exploited?

No, this vulnerability is not listed on the CISA Known Exploited Vulnerabilities (KEV) catalog and no public exploits are currently available.

What versions of Docker are affected by CVE-2026-34381?

The vulnerability exists in Admidio versions 5.0.0 through 5.0.7 when running in Docker containers with default Apache configuration. The fix is available in Admidio 5.0.8 and later.

How do I check if my server is vulnerable to CVE-2026-34381?

Run `docker exec <container_id> grep 'AllowOverride' /etc/apache2/sites-enabled/*.conf` and check if it shows 'AllowOverride None'. If true, and Admidio version is below 5.0.8, your system is vulnerable.

Does Defensia detect CVE-2026-34381?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Docker is installed on a monitored server, CVE-2026-34381 will appear in your dashboard with remediation steps.

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References

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