CVE-2024-10855
📋 TL;DR
This vulnerability in the Sirv WordPress plugin allows authenticated attackers with Contributor-level access or higher to delete arbitrary WordPress option values. This can be exploited to cause denial of service by deleting critical options that make the site inaccessible. All WordPress sites using Sirv plugin versions up to 7.3.0 are affected.
💻 Affected Systems
- Image Optimizer, Resizer and CDN – Sirv WordPress plugin
📦 What is this software?
Sirv by Sirv
⚠️ Risk & Real-World Impact
Worst Case
Complete site outage where legitimate users cannot access the WordPress site due to critical option deletion causing fatal errors.
Likely Case
Partial site functionality loss or specific features breaking due to deletion of non-critical options.
If Mitigated
Minimal impact if proper access controls and monitoring are in place to detect and block malicious option deletion attempts.
🎯 Exploit Status
Exploitation requires authenticated access but is straightforward once credentials are obtained. The vulnerability is publicly documented with code references.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 7.3.1
Vendor Advisory: https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=3186406%40sirv&new=3186406%40sirv&sfp_email=&sfph_mail=
Restart Required: No
Instructions:
1. Log into WordPress admin panel. 2. Navigate to Plugins → Installed Plugins. 3. Find 'Image Optimizer, Resizer and CDN – Sirv'. 4. Click 'Update Now' if available, or manually update to version 7.3.1 or later. 5. Verify plugin is active and functioning.
🔧 Temporary Workarounds
Disable Sirv plugin
allTemporarily deactivate the vulnerable plugin until patched
wp plugin deactivate sirv
Restrict user roles
linuxRemove Contributor and higher roles from untrusted users
wp user list --role=contributor --field=ID | xargs wp user set-role subscriber
🧯 If You Can't Patch
- Implement strict access controls to limit Contributor and higher roles to trusted users only
- Enable WordPress security plugins with file integrity monitoring and user activity logging
🔍 How to Verify
Check if Vulnerable:
Check WordPress admin → Plugins → Installed Plugins, find Sirv plugin and verify version is 7.3.0 or earlierCheck Version:
wp plugin get sirv --field=versionVerify Fix Applied:
Verify Sirv plugin version is 7.3.1 or later in WordPress admin panel📡 Detection & Monitoring
Log Indicators:
- WordPress audit logs showing option deletion by Contributor+ users
- PHP error logs showing missing option errors
Network Indicators:
- HTTP POST requests to /wp-admin/admin-ajax.php with action=sirv_upload_file_by_chunks
SIEM Query:
source="wordpress.log" (action="deleted_option" OR action="updated_option") AND user_role IN ("contributor", "author", "editor", "administrator")🔗 References
- https://plugins.trac.wordpress.org/browser/sirv/tags/7.2.8/sirv.php#L4691
- https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=3186406%40sirv&new=3186406%40sirv&sfp_email=&sfph_mail=
- https://www.wordfence.com/threat-intel/vulnerabilities/id/d6ec09e5-4994-4d23-bf8e-26b64d5303fa?source=cve
