CVE-2023-37534
📋 TL;DR
This vulnerability in HCL Leap allows attackers to inject malicious scripts through query parameters due to insufficient URI protocol whitelisting. This enables cross-site scripting (XSS) attacks against users of affected HCL Leap installations. Organizations using vulnerable versions of HCL Leap are affected.
💻 Affected Systems
- HCL Leap
📦 What is this software?
Hcl Leap by Hcltech
⚠️ Risk & Real-World Impact
Worst Case
Attackers could execute arbitrary JavaScript in victims' browsers, potentially stealing session cookies, performing actions as authenticated users, or redirecting to malicious sites.
Likely Case
Attackers craft malicious links containing script payloads in query parameters, which execute when victims click them, leading to session hijacking or credential theft.
If Mitigated
With proper input validation and output encoding, script execution would be prevented, limiting impact to benign parameter manipulation.
🎯 Exploit Status
XSS vulnerabilities are commonly exploited and require minimal technical skill when public details are available.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: HCL Leap 2023.2.1
Vendor Advisory: https://support.hcl-software.com/csm?id=kb_article&sysparm_article=KB0119900
Restart Required: Yes
Instructions:
1. Download HCL Leap 2023.2.1 from HCL support portal. 2. Backup current installation. 3. Apply the update following HCL Leap upgrade documentation. 4. Restart the application server.
🔧 Temporary Workarounds
Input Validation Filter
allImplement server-side validation to sanitize query parameters containing URI protocols
Web Application Firewall Rules
allConfigure WAF to block requests containing suspicious script patterns in query parameters
🧯 If You Can't Patch
- Isolate HCL Leap instances behind reverse proxies with strict input filtering
- Implement Content Security Policy (CSP) headers to restrict script execution sources
🔍 How to Verify
Check if Vulnerable:
Check HCL Leap version via administrative interface or configuration files. If version is earlier than 2023.2.1, system is vulnerable.Check Version:
Check HCL Leap version in administrative console or review installation directory version filesVerify Fix Applied:
After patching, verify version shows 2023.2.1 or later in administrative interface.📡 Detection & Monitoring
Log Indicators:
- Unusual query parameters containing script tags or JavaScript in access logs
- Multiple failed parameter validation attempts
Network Indicators:
- HTTP requests with encoded script payloads in query strings
- Unusual redirect patterns from HCL Leap endpoints
SIEM Query:
source="hcl_leap_logs" AND (uri_query="*script*" OR uri_query="*javascript:*" OR uri_query="*data:*")