CVE-2024-9891
📋 TL;DR
This vulnerability allows authenticated WordPress users with Subscriber-level access or higher to deactivate the Multiline files upload for contact form 7 plugin without proper authorization. Attackers can also submit custom reasons for deactivation. All WordPress sites using this plugin up to version 2.8.1 are affected.
💻 Affected Systems
- Multiline files upload for contact form 7 WordPress plugin
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Malicious authenticated users disable the plugin, disrupting file upload functionality for contact forms and potentially enabling further attacks by removing security controls.
Likely Case
Low-privilege users deactivate the plugin, causing service disruption for file uploads in contact forms and requiring administrator intervention to restore functionality.
If Mitigated
With proper user role management and monitoring, impact is limited to minor service disruption that can be quickly detected and remediated.
🎯 Exploit Status
Exploitation requires authenticated access but is simple to execute once authenticated. The vulnerability is publicly documented with code references.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2.8.2 or later
Vendor Advisory: https://plugins.trac.wordpress.org/changeset/3169228/
Restart Required: No
Instructions:
1. Log into WordPress admin panel. 2. Navigate to Plugins → Installed Plugins. 3. Find 'Multiline files upload for contact form 7'. 4. Click 'Update Now' if update is available. 5. Alternatively, download version 2.8.2+ from WordPress plugin repository and manually update.
🔧 Temporary Workarounds
Remove vulnerable plugin
allTemporarily deactivate and remove the plugin until patched version is available
wp plugin deactivate multiline-files-for-contact-form-7
wp plugin delete multiline-files-for-contact-form-7
Restrict user roles
allTemporarily restrict Subscriber and other low-privilege user access to the site
wp user list --role=subscriber --field=ID | xargs wp user set-role {ID} none
🧯 If You Can't Patch
- Implement strict user role management and monitor for unauthorized plugin deactivation attempts
- Deploy web application firewall rules to block requests to the vulnerable function endpoint
🔍 How to Verify
Check if Vulnerable:
Check WordPress admin panel → Plugins → Installed Plugins → Multiline files upload for contact form 7 → Version. If version is 2.8.1 or lower, you are vulnerable.Check Version:
wp plugin get multiline-files-for-contact-form-7 --field=versionVerify Fix Applied:
After updating, verify plugin version is 2.8.2 or higher in WordPress admin panel. Test that authenticated users cannot deactivate the plugin without proper permissions.📡 Detection & Monitoring
Log Indicators:
- WordPress logs showing plugin deactivation by non-admin users
- Apache/Nginx logs with POST requests to plugin deactivation endpoints from non-admin users
Network Indicators:
- HTTP POST requests to /wp-admin/admin-ajax.php with action=mfcf7_zl_custom_handle_deactivation_plugin_form_submission
SIEM Query:
source="wordpress.log" AND "plugin deactivated" AND user_role!="administrator"