CVE-2025-54321
📋 TL;DR
Ascertia SigningHub versions through 8.6.8 have a rate limiting vulnerability in the password reset function. Authenticated attackers can automate password reset requests to flood user email inboxes, causing denial of service and potential account lockouts. This affects all organizations using vulnerable SigningHub installations.
💻 Affected Systems
- Ascertia SigningHub
📦 What is this software?
Signinghub by Ascertia
⚠️ Risk & Real-World Impact
Worst Case
Massive email bombing campaigns could overwhelm email servers, cause denial of service for legitimate users, and potentially lead to account lockouts or service disruption.
Likely Case
Targeted email bombing against specific users causing inbox overflow, productivity loss, and potential missed important communications.
If Mitigated
Minimal impact with proper rate limiting and monitoring in place.
🎯 Exploit Status
Exploitation requires authenticated access. Public proof-of-concept code exists on GitHub.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 8.6.9 or later
Vendor Advisory: https://www.ascertia.com/company/vulnerability-disclosure-policy/
Restart Required: Yes
Instructions:
1. Download latest SigningHub version from Ascertia portal. 2. Backup current installation. 3. Apply patch/upgrade to version 8.6.9+. 4. Restart SigningHub services. 5. Verify functionality.
🔧 Temporary Workarounds
Implement WAF Rate Limiting
allConfigure web application firewall to limit password reset requests per IP/user
Email Filtering Rules
allCreate email server rules to detect and filter mass password reset emails
🧯 If You Can't Patch
- Implement network-level rate limiting for password reset endpoints
- Monitor for unusual patterns of password reset requests in application logs
🔍 How to Verify
Check if Vulnerable:
Check SigningHub version in admin panel. If version is 8.6.8 or earlier, system is vulnerable.Check Version:
Check admin dashboard or application configuration files for version informationVerify Fix Applied:
Verify version is 8.6.9 or later in admin panel. Test password reset function with multiple rapid requests to confirm rate limiting.📡 Detection & Monitoring
Log Indicators:
- Multiple password reset requests from same user/IP in short timeframe
- Unusual spike in password reset activity
Network Indicators:
- High volume of POST requests to password reset endpoint
- Pattern of requests with same parameters
SIEM Query:
source="signinghub" AND (event="password_reset_request" OR url_path="/reset-password") | stats count by src_ip, user | where count > 10