CVE-2020-15231
📋 TL;DR
This vulnerability in mapfish-print allows attackers to exploit JSONP support to execute cross-site scripting (XSS) attacks. Users of mapfish-print versions before 3.24 are affected, potentially enabling attackers to steal session cookies, redirect users, or perform actions on their behalf.
💻 Affected Systems
- mapfish-print
📦 What is this software?
Print by Mapfish
⚠️ Risk & Real-World Impact
Worst Case
Attackers could steal administrator credentials, compromise user accounts, deface websites, or redirect users to malicious sites, potentially leading to full system compromise.
Likely Case
Attackers inject malicious scripts to steal user session cookies or credentials, enabling account takeover and unauthorized access to sensitive data.
If Mitigated
With proper input validation and output encoding, the impact is limited to minor data exposure or temporary service disruption.
🎯 Exploit Status
XSS via JSONP is a well-known attack vector with public proof-of-concept available in the advisory.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 3.24
Vendor Advisory: https://github.com/mapfish/mapfish-print/security/advisories/GHSA-w534-q4xf-h5v2
Restart Required: Yes
Instructions:
1. Update mapfish-print to version 3.24 or later. 2. Restart the mapfish-print service. 3. Verify the fix by checking the version and testing JSONP functionality.
🔧 Temporary Workarounds
Disable JSONP Support
allDisable JSONP functionality in mapfish-print configuration to prevent exploitation.
Modify configuration to set jsonp.enabled=false
Implement Content Security Policy
allAdd Content-Security-Policy headers to restrict script execution sources.
Add 'Content-Security-Policy: script-src 'self'' to HTTP headers
🧯 If You Can't Patch
- Implement strict input validation and output encoding for all user-supplied data
- Deploy a web application firewall (WAF) with XSS protection rules
🔍 How to Verify
Check if Vulnerable:
Check mapfish-print version. If version is below 3.24 and JSONP is enabled, the system is vulnerable.Check Version:
Check application logs or configuration files for version information, or use: curl -v http://your-mapfish-print-server/versionVerify Fix Applied:
Verify mapfish-print version is 3.24 or later and test JSONP endpoints for XSS vulnerabilities.📡 Detection & Monitoring
Log Indicators:
- Unusual JSONP requests with script tags or JavaScript payloads
- Multiple failed JSONP requests from same source
Network Indicators:
- HTTP requests containing <script> tags in JSONP parameters
- Unusual traffic patterns to JSONP endpoints
SIEM Query:
source="mapfish-print" AND (uri="*jsonp*" OR uri="*callback=*") AND (content="<script>" OR content="javascript:")🔗 References
- https://github.com/mapfish/mapfish-print/pull/1397/commits/89155f2506b9cee822e15ce60ccae390a1419d5e
- https://github.com/mapfish/mapfish-print/security/advisories/GHSA-w534-q4xf-h5v2
- https://github.com/mapfish/mapfish-print/pull/1397/commits/89155f2506b9cee822e15ce60ccae390a1419d5e
- https://github.com/mapfish/mapfish-print/security/advisories/GHSA-w534-q4xf-h5v2
