CVE-2026-2947
📋 TL;DR
This CVE describes a cross-site scripting (XSS) vulnerability in rymcu forest versions up to 0.0.5. Attackers can inject malicious scripts via the updateUserInfo function in the user profile handler, potentially compromising user sessions or stealing sensitive data. All users of affected versions are at risk.
💻 Affected Systems
- rymcu forest
📦 What is this software?
Forest by Rymcu
⚠️ Risk & Real-World Impact
Worst Case
Attackers could steal user session cookies, perform actions as authenticated users, or redirect users to malicious sites, potentially leading to account takeover and data theft.
Likely Case
Attackers inject malicious JavaScript that executes in victims' browsers, potentially stealing session tokens or displaying phishing content to users.
If Mitigated
With proper input validation and output encoding, the impact is limited to minor UI disruption or blocked script execution.
🎯 Exploit Status
Exploit is publicly available and can be executed remotely, though authentication may be required to access the vulnerable endpoint.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: None available
Restart Required: No
Instructions:
No official patch available. Consider upgrading to a version above 0.0.5 if available, or implement workarounds.
🔧 Temporary Workarounds
Input Validation and Output Encoding
allImplement server-side validation of user inputs and encode outputs to prevent script execution.
Implement input validation in src/main/java/com/rymcu/forest/web/api/user/UserInfoController.java
Content Security Policy (CSP)
allDeploy a strict CSP header to mitigate XSS impact by restricting script sources.
Add Content-Security-Policy header to web server configuration
🧯 If You Can't Patch
- Implement a web application firewall (WAF) with XSS protection rules
- Disable or restrict access to the vulnerable updateUserInfo endpoint if not essential
🔍 How to Verify
Check if Vulnerable:
Check if running rymcu forest version 0.0.5 or earlier. Review the UserInfoController.java file for lack of input sanitization in updateUserInfo.Check Version:
Check application version in configuration files or via application metadata.Verify Fix Applied:
Test the updateUserInfo endpoint with XSS payloads to ensure they are properly sanitized or blocked.📡 Detection & Monitoring
Log Indicators:
- Unusual POST requests to user update endpoints with script-like payloads
- Error logs showing script execution attempts
Network Indicators:
- HTTP requests containing script tags or JavaScript in user profile update parameters
SIEM Query:
Search for POST requests to */api/user/* containing <script> or javascript: patterns