CVE-2020-15789
📋 TL;DR
CVE-2020-15789 is a Cross-Site Request Forgery (CSRF) vulnerability in Polarion Subversion Webclient that allows attackers to trick authenticated users into performing unauthorized actions. If exploited, attackers could read or modify web application content. This affects all versions of Polarion Subversion Webclient.
💻 Affected Systems
- Polarion Subversion Webclient
📦 What is this software?
⚠️ 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
Attacker gains full control over the web application's content, allowing data theft, modification, or deletion of all accessible resources.
Likely Case
Attacker modifies or deletes specific repository content, potentially disrupting development workflows or stealing intellectual property.
If Mitigated
Limited impact with proper CSRF protections, though some risk remains if users click malicious links while authenticated.
🎯 Exploit Status
Exploitation requires social engineering to trick authenticated users into clicking malicious links.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Check Siemens advisory for specific patched versions
Vendor Advisory: https://cert-portal.siemens.com/productcert/pdf/ssa-436520.pdf
Restart Required: Yes
Instructions:
1. Review Siemens advisory SSA-436520
2. Apply vendor-provided patches
3. Restart affected services
4. Verify CSRF protections are enabled
🔧 Temporary Workarounds
Implement CSRF Tokens
allAdd anti-CSRF tokens to all state-changing requests
Configuration depends on specific deployment - consult Polarion documentation
SameSite Cookie Attribute
allSet SameSite=Strict or Lax attributes on session cookies
Set-Cookie: session=value; SameSite=Strict; Secure; HttpOnly
🧯 If You Can't Patch
- Implement web application firewall with CSRF protection rules
- Restrict access to web interface to trusted networks only
🔍 How to Verify
Check if Vulnerable:
Check if Polarion Subversion Webclient is running without CSRF protections enabledCheck Version:
Check Polarion administration interface or consult system documentationVerify Fix Applied:
Verify CSRF tokens are required for all POST/PUT/DELETE requests and SameSite cookie attributes are set📡 Detection & Monitoring
Log Indicators:
- Multiple failed state-changing requests from same user
- Requests missing expected CSRF tokens
- Unusual modification patterns in repository
Network Indicators:
- HTTP requests with Referer headers pointing to external domains
- POST requests without corresponding GET requests from same session
SIEM Query:
web_requests WHERE (method IN ('POST', 'PUT', 'DELETE')) AND csrf_token IS NULL AND user_authenticated = true