CVE-2025-62752
📋 TL;DR
This DOM-based Cross-Site Scripting (XSS) vulnerability in the Calendar.Online/Kalender.Digital WordPress plugin allows attackers to inject malicious scripts into web pages viewed by other users. It affects all versions up to 1.0.11 of the plugin. WordPress site administrators using this plugin are affected.
💻 Affected Systems
- Calendar.Online / Kalender.Digital 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
Attackers could steal administrator session cookies, perform actions as authenticated users, deface websites, or redirect users to malicious sites.
Likely Case
Attackers inject malicious scripts to steal user session data or credentials when users visit compromised pages.
If Mitigated
With proper Content Security Policy (CSP) headers and input validation, impact is limited to script execution in specific contexts.
🎯 Exploit Status
DOM-based XSS typically requires user interaction but can be exploited via crafted links or stored inputs.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.0.12 or later
Restart Required: No
Instructions:
1. Log into WordPress admin panel. 2. Navigate to Plugins > Installed Plugins. 3. Find 'Calendar.Online / Kalender.Digital'. 4. Click 'Update Now' if available. 5. Alternatively, download version 1.0.12+ from WordPress repository and replace plugin files.
🔧 Temporary Workarounds
Disable Plugin
allTemporarily disable the vulnerable plugin until patched.
wp plugin deactivate kalender-digital
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 Calendar.Online/Kalender.Digital plugin immediately.
- Implement web application firewall (WAF) rules to block XSS payloads.
🔍 How to Verify
Check if Vulnerable:
Check WordPress admin > Plugins > Installed Plugins for Calendar.Online/Kalender.Digital version 1.0.11 or earlier.Check Version:
wp plugin get kalender-digital --field=versionVerify Fix Applied:
Verify plugin version is 1.0.12 or later in WordPress admin panel.📡 Detection & Monitoring
Log Indicators:
- Unusual POST/GET requests with script tags or JavaScript payloads to plugin endpoints.
- Multiple failed login attempts following suspicious page visits.
Network Indicators:
- HTTP requests containing <script> tags or JavaScript code in parameters.
- Outbound connections to unknown domains from user browsers.
SIEM Query:
source="web_server" AND (uri="*kalender*" OR uri="*calendar*" OR user_agent="*script*" OR http_request="*<script>*")