CVE-2025-50891
📋 TL;DR
This vulnerability allows attackers to inject HTML or execute arbitrary code via cookie hijacking in Adform Site Tracking server-side backend. It affects customers using Adform Site Tracking before 2025-08-28. The vulnerability is a reflected cross-site scripting (XSS) issue that can be exploited without user interaction.
💻 Affected Systems
- Adform Site Tracking
⚠️ 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 execute arbitrary JavaScript in victims' browsers, potentially stealing session cookies, performing actions on behalf of users, or delivering malware.
Likely Case
Session hijacking, credential theft, or defacement of web pages through injected content.
If Mitigated
Limited impact with proper input validation and output encoding in place.
🎯 Exploit Status
Public proof-of-concept available on GitHub. Exploitation requires cookie hijacking but no authentication.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2025-08-28 or later
Vendor Advisory: https://www.adformhelp.com/hc/en-us/categories/9738364537233-Adform-Site-Tracking
Restart Required: No
Instructions:
1. Contact Adform support to ensure your Site Tracking backend is updated to version dated 2025-08-28 or later. 2. Verify the update has been applied to your account.
🔧 Temporary Workarounds
Implement Content Security Policy
allAdd CSP headers to restrict script execution from untrusted sources
Content-Security-Policy: default-src 'self'; script-src 'self'
Cookie Security Headers
allSet HttpOnly and Secure flags on cookies to prevent JavaScript access
Set-Cookie: session=abc123; HttpOnly; Secure; SameSite=Strict
🧯 If You Can't Patch
- Implement WAF rules to block XSS payloads in cookies and request parameters
- Monitor for unusual cookie values or JavaScript execution patterns in logs
🔍 How to Verify
Check if Vulnerable:
Check if your Adform Site Tracking backend version is before 2025-08-28 by contacting Adform support or checking your account settings.Check Version:
Contact Adform support as this is a cloud service, not locally installed software.Verify Fix Applied:
Confirm with Adform that your backend has been updated to 2025-08-28 or later version.📡 Detection & Monitoring
Log Indicators:
- Unusual cookie values containing script tags or JavaScript code
- Multiple failed requests with XSS payloads in cookies
Network Indicators:
- HTTP requests with suspicious cookie values containing <script> tags or JavaScript functions
SIEM Query:
source="web_logs" AND (cookie="*<script>*" OR cookie="*javascript:*" OR cookie="*onload=*" OR cookie="*onerror=*")