CVE-2024-11335
📋 TL;DR
This vulnerability allows authenticated WordPress users with contributor-level access or higher to inject malicious scripts via the UltraEmbed plugin's iframe shortcode. The scripts are stored and execute whenever other users view affected pages, enabling session hijacking, defacement, or malware distribution. All WordPress sites using UltraEmbed plugin versions up to 1.0.3 are affected.
💻 Affected Systems
- UltraEmbed – Advanced Iframe Plugin For WordPress with Gutenberg Block Included
⚠️ 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
Attackers could steal administrator credentials, install backdoors, redirect users to malicious sites, or completely compromise the WordPress site and potentially the underlying server.
Likely Case
Attackers inject malicious JavaScript to steal user sessions, display unwanted content, or redirect users to phishing pages, leading to data theft and reputational damage.
If Mitigated
With proper user access controls and content security policies, impact is limited to defacement or minor content manipulation within the affected pages.
🎯 Exploit Status
Exploitation requires authenticated access but is technically simple. Public proof-of-concept exists showing how to inject scripts via iframe attributes.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.0.4 or later
Vendor Advisory: https://wordpress.org/plugins/ultraembed-advanced-iframe/
Restart Required: No
Instructions:
1. Log into WordPress admin panel. 2. Navigate to Plugins → Installed Plugins. 3. Find UltraEmbed plugin. 4. Click 'Update Now' if update is available. 5. Alternatively, download version 1.0.4+ from WordPress repository and manually update.
🔧 Temporary Workarounds
Remove Contributor Posting Capabilities
allTemporarily restrict contributor-level users from creating or editing posts to prevent exploitation.
Use WordPress role management plugins or custom code to modify user capabilities
Disable UltraEmbed Plugin
linuxDeactivate the vulnerable plugin until patched, though this will break iframe functionality.
wp plugin deactivate ultraembed-advanced-iframe
🧯 If You Can't Patch
- Implement strict Content Security Policy (CSP) headers to block inline script execution
- Regularly audit user accounts and remove unnecessary contributor-level access
🔍 How to Verify
Check if Vulnerable:
Check WordPress admin panel → Plugins → UltraEmbed plugin version. If version is 1.0.3 or lower, you are vulnerable.Check Version:
wp plugin get ultraembed-advanced-iframe --field=versionVerify Fix Applied:
After updating, verify plugin version shows 1.0.4 or higher in WordPress plugins list.📡 Detection & Monitoring
Log Indicators:
- Unusual iframe shortcode modifications in post/page edits
- Multiple post updates from contributor-level users
- Script tags containing malicious domains in post content
Network Indicators:
- Outbound connections to suspicious domains from WordPress pages
- Unexpected JavaScript loading from post content
SIEM Query:
source="wordpress" AND (event="post_updated" OR event="page_updated") AND user_role="contributor" AND content CONTAINS "[iframe"