CVE-2025-66453
📋 TL;DR
This vulnerability in Rhino JavaScript engine allows attackers to cause high CPU consumption and potential Denial of Service by passing specially crafted floating-point numbers to the toFixed() function. Applications using vulnerable Rhino versions for JavaScript processing are affected, particularly those that process untrusted user input.
💻 Affected Systems
- Mozilla Rhino JavaScript Engine
⚠️ 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
Complete service unavailability due to CPU exhaustion, potentially affecting all users of the application.
Likely Case
Degraded performance and intermittent service disruptions when attackers trigger the CPU-intensive calculation.
If Mitigated
Minimal impact with proper input validation and resource limits in place.
🎯 Exploit Status
Exploitation requires ability to pass numeric input to toFixed() function.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.8.1, 1.7.15.1, or 1.7.14.1
Vendor Advisory: https://github.com/mozilla/rhino/security/advisories/GHSA-3w8q-xq97-5j7x
Restart Required: Yes
Instructions:
1. Identify Rhino version in use. 2. Update to patched version: 1.8.1, 1.7.15.1, or 1.7.14.1. 3. Rebuild and redeploy applications using Rhino. 4. Restart affected services.
🔧 Temporary Workarounds
Input Validation
allValidate and sanitize all numeric inputs before passing to toFixed() function.
Resource Limits
allImplement CPU usage limits and timeouts for JavaScript execution.
🧯 If You Can't Patch
- Implement strict input validation to reject suspicious floating-point numbers.
- Deploy rate limiting and monitoring to detect DoS attempts.
🔍 How to Verify
Check if Vulnerable:
Check Rhino version in application dependencies or classpath. Versions before 1.8.1, 1.7.15.1, and 1.7.14.1 are vulnerable.Check Version:
Check Maven/Gradle dependencies or examine rhino.jar manifest: java -jar rhino.jar --versionVerify Fix Applied:
Confirm updated to Rhino 1.8.1, 1.7.15.1, or 1.7.14.1 in dependencies.📡 Detection & Monitoring
Log Indicators:
- Unusually high CPU usage spikes
- JavaScript execution timeouts
- Repeated toFixed() calls with similar inputs
Network Indicators:
- Increased traffic to endpoints processing numeric input
- Pattern of requests with floating-point parameters
SIEM Query:
source="application_logs" AND ("CPU spike" OR "timeout" OR "toFixed")