CVE-2025-26998
📋 TL;DR
This stored cross-site scripting (XSS) vulnerability in the SKT Blocks WordPress plugin allows attackers to inject malicious scripts into web pages. When users view pages containing the malicious content, their browsers execute the scripts, potentially compromising their accounts or sessions. All WordPress sites using SKT Blocks versions up to 1.8 are affected.
💻 Affected Systems
- SKT Blocks – Gutenberg based Page Builder WordPress plugin
📦 What is this software?
Skt Blocks by Sktthemes
⚠️ Risk & Real-World Impact
Worst Case
Attackers could steal administrator credentials, take over websites, deface content, redirect visitors to malicious sites, or install backdoors for persistent access.
Likely Case
Attackers inject malicious JavaScript to steal user session cookies, perform actions on behalf of authenticated users, or redirect users to phishing pages.
If Mitigated
With proper input validation and output encoding, malicious scripts would be neutralized before reaching users' browsers.
🎯 Exploit Status
Stored XSS vulnerabilities are commonly exploited. While no public PoC is confirmed, the vulnerability type is well-understood and easily weaponized.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.9 or later
Restart Required: No
Instructions:
1. Log into WordPress admin panel. 2. Navigate to Plugins → Installed Plugins. 3. Find 'SKT Blocks – Gutenberg based Page Builder'. 4. Click 'Update Now' if available. 5. Alternatively, download version 1.9+ from WordPress repository and manually update.
🔧 Temporary Workarounds
Disable vulnerable plugin
allTemporarily disable the SKT Blocks plugin until patched
wp plugin deactivate skt-blocks
Implement Content Security Policy
allAdd CSP headers to restrict script execution sources
Add to .htaccess: Header set Content-Security-Policy "default-src 'self'; script-src 'self'"
Add to nginx config: add_header Content-Security-Policy "default-src 'self'; script-src 'self'";
🧯 If You Can't Patch
- Disable the SKT Blocks plugin immediately
- Implement web application firewall (WAF) rules to block XSS payloads
🔍 How to Verify
Check if Vulnerable:
Check WordPress admin → Plugins → SKT Blocks version. If version is 1.8 or lower, you are vulnerable.Check Version:
wp plugin get skt-blocks --field=versionVerify Fix Applied:
Verify plugin version is 1.9 or higher in WordPress admin panel.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to WordPress admin-ajax.php or admin-post.php containing script tags
- Multiple failed login attempts following suspicious content updates
Network Indicators:
- Outbound connections to unknown domains from WordPress server
- Unexpected JavaScript includes in page responses
SIEM Query:
source="wordpress.log" AND ("skt-blocks" OR "admin-ajax.php") AND ("<script>" OR "javascript:" OR "onerror=" OR "onload=")