Arbitrary Content Deletion (IDOR) in Media Library Folders Plugin — What Every WordPress Admin Should Do Now

Author: WP-Firewall Security Team

Date: 2026-02-14

Tags: WordPress, Security, WAF, Vulnerability, Media Library, IDOR

Summary: A recently disclosed insecure direct object reference (IDOR) vulnerability affecting Media Library Folders (all versions ≤ 8.3.6) allows authenticated users with Author-level privileges to delete or rename attachments that they do not own. This post explains the technical details, real-world risk, detection and remediation steps, recommended temporary mitigations, and how WP-Firewall protects you — including a free plan you can enable today to get immediate mitigation.

Executive summary

On 13 Feb 2026 a vulnerability affecting the WordPress plugin “Media Library Folders” (versions ≤ 8.3.6) was disclosed (CVE-2026-2312). The issue is an insecure direct object reference (IDOR) that permits an authenticated user with Author-level privileges (or above) to delete or rename arbitrary attachments across the site. The plugin author released a fixed version 8.3.7. The vulnerability is rated with a CVSS 3.1 score of 4.3 (Low), but this does not mean it’s harmless. Attackers with an Author account (or compromised Author credentials) can remove media assets, break pages that reference those assets, and cause content disruption or reputational harm.

If your site uses Media Library Folders and you have Authors on the site, update the plugin immediately. If you cannot update right away, deploy temporary mitigations described below and use a Web Application Firewall (WAF) that provides virtual patching and rule-based protections.

Why this matters (plain language)

WordPress stores uploaded pictures, PDFs, and other media as “attachment” objects. When a plugin fails to verify that the user requesting a change actually owns — or is allowed to modify — an attachment, an authenticated user can manipulate the ID or other request parameters and modify or delete files they shouldn’t be able to touch.

Think of it this way: the plugin gave Authors the ability to operate on attachments by ID without checking ownership. An Author can normally only manage their own media, but because of the missing check they can now delete or rename any attachment by sending the right request. The damage is straightforward: missing images, broken pages, lost downloadable assets, and time-consuming content recovery.

Technical overview of the vulnerability (IDOR)

• Vulnerability type: Insecure Direct Object Reference (IDOR) / Broken Access Control.
• Affected component: Media Library Folders plugin for WordPress, versions ≤ 8.3.6.
• Fixed in: 8.3.7.
• CVE: CVE-2026-2312.
• CVSS: 3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N (score 4.3).
• Required privilege: Author (authenticated).
• Attack vector: Network (authenticated request to the plugin’s action endpoint).
• Impact: Arbitrary deletion or rename of attachments (integrity loss of media assets).

What “IDOR” means in this case:

• The plugin exposes an action (for example, a backend AJAX or admin POST request) that accepts an attachment identifier (post ID or file ID) and performs deletion/rename.
• The code fails to verify that the current user has the right ownership or permission for that particular attachment.
• As long as the attacker is an authenticated user with Author-level privileges, they can perform the action on arbitrary IDs and delete or rename attachments belonging to other users.

Important nuance: Authors already have some privileges (e.g., publish posts or upload media). This vulnerability extends those privileges improperly to attachments they do not own.

How an attacker could exploit this (high-level, non-exploitable PoC)

I will not publish a working exploit here. Below is a high-level, conceptual flow showing how the vulnerability can be abused so admins understand the risk and detection signals to watch for.

1. Attacker signs in (or already is an Author on the site, or gains Author credentials via phishing/credential reuse).
2. Attacker crafts an authenticated HTTP request to the plugin’s action endpoint responsible for delete/rename (the plugin exposes server-side endpoints to manage media).
3. The request includes an attachment identifier (attachment_post_ID) that belongs to another user or a critical site asset (e.g., site logo, hero images, product images).
4. The plugin processes the request without confirming that the logged-in user owns the attachment or has site-wide delete rights.
5. The plugin deletes or renames the attachment. The file is removed from the uploads directory and/or the database entry is deleted/updated.
6. The attacker repeats for multiple assets to cause widespread content removal.

Because the attacker needs to be authenticated at the Author level (or higher), external anonymous visitors cannot directly trigger it. However, social engineering, compromised accounts, or weak user management can still make this high-impact.

Real-world impact scenarios

• A malicious or compromised Author deletes all product images on an e-commerce site. Product pages display broken images and conversions drop.
• An Author renames or deletes press images and case study PDFs. Marketing pages show missing resources and business reputation degrades.
• A compromised Author account is used to remove blog header images, causing visual disruption and a poor user experience.
• Repeated deletions can remove images that are not present in backups (if backups are infrequent), causing permanent loss.

Even though CVSS rates confidentiality and system availability impacts as low, the integrity effect (deleted assets) can disrupt business-critical workflows. For publishers, agencies, and shops, the operational cost and reputational damage can be substantial.

Immediate actions (step-by-step)

If you use Media Library Folders on any live site, follow these immediate steps:

1. Update now
   Update the plugin to version 8.3.7 or later. This is the single most important action.
   Test update in staging first for high-traffic mission-critical sites, then update production.
2. If you cannot update immediately:
   Deactivate the plugin on the production site until you can patch. This will remove functionality but prevents the vulnerability from being abused.
   Limit Author privileges. Temporarily restrict user roles that have upload or author-level privileges until the plugin is updated.
3. Enable your WAF:
   Deploy a Web Application Firewall in front of the site (WP-Firewall customers can enable specific virtual patching rules). The WAF can block the specific request patterns targeting the vulnerable endpoints.
4. Monitor logs:
   Check web server and WordPress logs for suspicious delete/rename requests to plugin endpoints.
   Look for a spike in 200/POST requests to the plugin’s admin endpoints coming from Author accounts.
5. Backups:
   Ensure you have a recent full backup (files + database). If media has already been deleted, restore from backup.
   If you use incremental backups, check the retention points and prepare to restore affected media assets.

Detection guidance — what to look for

1. WordPress audit logs
   Review who performed delete actions on attachments. A change in owner or a deletion performed by an Author for assets that they did not upload is suspicious.
2. Server access logs
   Search for POST/GET requests to admin-ajax.php or to plugin-specific admin endpoints containing parameters like attachment_id, file_id, action=...delete..., rename, etc.
   Look for requests made by Author sessions or from a single account performing many delete actions.
3. Database checks
   Query the wp_posts table for missing attachments:
   SELECT * FROM wp_posts WHERE post_type = 'attachment' ORDER BY post_date DESC;
   Track sudden drop in attachment count or gaps where previously-referenced attachments are missing.
4. Broken pages
   Use automated site crawlers or content checks to detect missing images (404s for files under wp-content/uploads).
   Monitor front-end error logs for missing assets referenced in posts/pages.
5. File system checks
   Compare uploads directory contents with database wp_posts attachments. Or use file integrity tools to detect removed files.

Example log pattern to search for (conceptual):

• POST /wp-admin/admin-ajax.php?action=mlplus_delete_attachment&id=12345 — performed by user ID 28
• Multiple POSTs in a short time from same user session deleting attachments with different IDs.

Do not assume that a single missing image is the result of this bug — correlate with request logs and user activity.

Recovery and incident response

1. Immediately patch the plugin (update to 8.3.7+) or deactivate it.
2. Revoke or reset credentials for the offending user(s). Rotate passwords and enforce MFA.
3. Restore deleted attachments from your most recent file + DB backup:
   Restore files to wp-content/uploads.
   If database attachment rows were removed, re-import or re-create attachment entries or restore the DB to a point prior to the deletion (can be combined with a selective import of the attachments table).
4. If no backup or partial backup exists:
   Search remote caches (CDN, Google cached pages) and other mirrors to recover assets.
   Check if media were stored in external storage (S3, remote buckets).
5. Conduct a post-incident analysis:
   How did the attacker gain Author-level access? Was it a compromised legitimate account?
   Review user lifecycle and authentication policies. Ensure least privilege.
   Implement monitoring to alert on suspicious author activity going forward.

Important: Replacing files alone may not restore the WordPress attachment records. Files must be re-associated with post entries in the database or re-uploaded via the Media Library (which re-creates proper metadata).

Temporary mitigation options (if you cannot immediately update)

If immediate plugin update is not possible, consider one or more of the following temporary measures — each has tradeoffs:

1. Deactivate the plugin
   Pros: Removes attack surface completely.
   Cons: Functionality loss; media folder organization features will be disabled.
2. Restrict Authors temporarily
   Remove the upload_files capability from Author accounts using a role editor plugin or via code. This prevents uploading and may block certain plugin behaviors.
   Downgrade Authors to Contributors temporarily if authors do not need publishing rights.
   Pros: Low technical impact on code.
   Cons: Affects editorial workflow.
3. Disable the vulnerable endpoints via server rules
   Use web server configuration (.htaccess, Nginx rules) to block HTTP methods or block specific plugin endpoints from being accessed except by administrators.
   Example conceptual rule: block requests containing specific query parameters or path segments associated with the plugin’s admin endpoints.
   Pros: Keeps plugin active while stopping the specific requests.
   Cons: Requires accurate identification of the endpoint paths; risk of false positives blocking legitimate admin usage.
4. WAF virtual patching
   Apply a rule to block suspicious POSTs to the plugin’s endpoints containing delete/rename actions for attachments unless the source is an admin user/role.
   Pros: Minimal site disruption; fast to deploy.
   Cons: Requires a capable WAF (virtual patch may not be perfect).
5. Change file permissions (not recommended unless you understand side effects)
   Make uploads directory temporarily read-only at the OS level to prevent file deletion.
   Pros: Prevents file deletion.
   Cons: Breaks uploads and may cause errors; not recommended for prolonged use.

Remember: temporary mitigations should be followed by a full patch and a security review.

Hardening recommendations (long-term)

1. Principle of least privilege
   Review roles and capabilities regularly. Avoid granting Author-level accounts more privileges than required.
2. Enforce multi-factor authentication (MFA)
   MFA significantly reduces the risk of compromised credentials for privileged users.
3. Limit number of Author-level accounts
   Keep the number of users who can publish/manage media minimal; use editorial workflows that avoid unnecessary privileged accounts.
4. Keep plugins and WordPress core up to date
   Regular updates drastically reduce exposure to known vulnerabilities.
5. Use a WAF with virtual patching and request inspection
   A WAF can provide immediate protection while you patch plugins, and can block suspicious request patterns (e.g., mass deletion).
6. Monitor and alert
   Implement logging for admin actions and set alerts for unusual activity (e.g., an Author performing mass deletions).
7. Maintain reliable backups (files + database)
   Test backups regularly and store offsite copies. Ensure backup frequency matches business needs.
8. Periodic security audits
   Regularly scan the site for plugin vulnerabilities and misconfigurations.

How WP-Firewall protects you (practical capabilities)

At WP-Firewall we approach this vulnerability with three simultaneous layers:

1. Rapid detection and push notification
   As soon as a vulnerability like this is disclosed, we analyze the plugin behavior and create detection rules for requests targeting the endpoints typically used by the plugin.
   We notify customers via email dashboard alerts and provide recommended steps (update/deactivate/apply mitigation).
2. Virtual patching via WAF rules
   WP-Firewall deploys rule sets that block suspicious requests (e.g., unauthenticated or low-privilege attempts to invoke delete/rename actions).
   For this specific class of IDOR, our virtual patch blocks POSTs and AJAX calls that contain deletion/rename parameters unless the session is an administrator or a verified trusted source.
3. Malware scanning and content integrity checks
   Our scanners detect unexpected removals and changes in the uploads directory and attachment records and can correlate them with recent activity to surface likely incidents.
   We also monitor for repeated deletion patterns from a specific user session.

Additional WP-Firewall features that help:

• Managed firewall with unlimited bandwidth and OWASP Top 10 mitigations.
• Malware scanner that looks for suspicious file operations.
• Auto-update options for vulnerable plugins (configure with care for test environments).
• Audit logs and alerts for admin/user activity (available in higher tiers).

If you are on our free plan, you already get basic managed firewall and malware scanner features that can reduce immediate risk; upgrading provides advanced virtual patching and response capabilities.

Detection templates and queries (for administrators)

Use these queries and log checks to hunt for signs of exploitation. Replace table prefixes as needed.

1. Quickly list attachments added/removed in a time window:

SELECT ID, post_title, post_date, post_author
FROM wp_posts
WHERE post_type = 'attachment'
ORDER BY post_date DESC
LIMIT 100;

2. Detect attachments deleted between timestamps (requires backups or auditing):

• Compare two exports of wp_posts (attachment rows) to identify missing rows.
• If you have auditing enabled (activity log plugin), search for operations like delete_attachment performed by user accounts.

3. Web server log search (conceptual / grep example):

# Search for admin-ajax or plugin endpoint with "delete" or "rename"
grep -E "admin-ajax.php.*(delete|rename|attachment|file_id)" /var/log/apache2/access.log

4. Look for a single user performing multiple delete operations:

# Use your audit logs or database activity logs to find high-frequency delete actions by same user id
# Pseudocode:
SELECT user_id, COUNT(*) as deletions
FROM audit_log
WHERE action LIKE '%delete_attachment%' AND timestamp >= '2026-02-01'
GROUP BY user_id
HAVING deletions > 5;

Safe code snippet: temporarily remove Author deletion capability

Caution: This change affects how Authors can manage their own posts and media. Test in staging first.

Add the following to a site-specific plugin or a mu-plugin to temporarily remove the delete_posts capability from Authors (so they cannot delete their attachments). This is a blunt instrument and will reduce their ability to manage content.

<?php
// mu-plugin: disable-author-delete.php
add_action('init', function() {
    $role = get_role('author');
    if ($role) {
        // Remove the ability to delete posts (and therefore attachments they own)
        // Reversible by removing this file or code.
        $role->remove_cap('delete_posts');
        $role->remove_cap('delete_published_posts');
    }
});

Alternative: remove upload_files capability from the Author role to prevent authors from uploading new files:

$role = get_role('author');
if ($role) {
    $role->remove_cap('upload_files');
}

Important: Both approaches affect editorial workflow. Use only as temporary mitigations until the plugin is patched.

After you patch: validate and harden

1. Confirm plugin is at 8.3.7+.
2. Re-enable any temporarily disabled functionality gradually.
3. Re-check logs for any suspicious activity after the patch to ensure no post-exploitation.
4. Rotate credentials for users affected and enforce MFA.
5. Run a full site scan (file + DB) to verify no further tampering.

Frequently asked questions

Q: If a site has no Authors, am I safe?
A: If there are no users with Author-level privileges (or higher), the direct attack path requiring Author auth is mitigated. However, if Author accounts exist on any site instance (staging, contributors that were upgraded, etc.), treat them as potential exits for exploitation. Also, attackers can try to elevate lower-level accounts through other vulnerabilities.

Q: Will deactivating the plugin break my site?
A: Deactivation will disable the folder organization features. Your media files remain in the uploads directory, but the plugin’s UI and organization functionality will be unavailable until you reactivate the updated plugin.

Q: Does this mean my files are gone forever if deleted?
A: Not necessarily. If you have file + DB backups, you can restore. If there are no backups, recovery can be difficult; check CDN caches and external backups.

How to prioritize this risk

• If your site relies on many Authors and public-facing media, prioritize updating immediately.
• Sites with a single Admin and no lower-privileged content editors are lower risk but still should update.
• E-commerce, membership, and high-traffic editorial sites should deploy WAF mitigations and audit activity closely.

Protect your site today — Start free with WP-Firewall Basic

Secure your WordPress site in minutes with WP-Firewall Basic (Free). It provides essential managed firewall protection, unlimited bandwidth, a robust WAF, automated malware scanning, and mitigations for OWASP Top 10 risks — everything you need to reduce exposure and buy time to apply patches when vulnerabilities like this appear.

• Basic (Free): managed firewall, unlimited bandwidth, WAF, malware scanner, OWASP Top 10 mitigation.
• Standard ($50/year): adds automatic malware removal and the ability to blacklist/whitelist up to 20 IPs.
• Pro ($299/year): adds monthly security reports, automatic virtual patching, and premium support/add-ons.

Get started on the free plan and protect your media and pages from vulnerabilities while you patch: https://my.wp-firewall.com/buy/wp-firewall-free-plan/

Final notes from WP-Firewall Security

This IDOR in Media Library Folders is fixable by a plugin update, but it underlines a persistent theme: WordPress sites must operate with least privilege, a layered defense model, and reliable backups. A vulnerability that looks “low severity” on a CVSS score still translates into real-world business disruption when assets are deleted or content is broken.

If you need assistance applying temporary mitigations, implementing a WAF rule, or recovering media assets, WP-Firewall’s support team can help. For quick protection, enable WP-Firewall Basic and let our managed WAF provide virtual patching and monitoring while you patch plugins and take corrective actions.

Stay safe, and audit your plugins — especially those that manage media or file operations — regularly.