CVE-2025-68475
📋 TL;DR
This CVE describes a Regular Expression Denial of Service (ReDoS) vulnerability in Fedify's document loader. Attackers can cause catastrophic backtracking by sending maliciously crafted HTML responses, leading to excessive CPU consumption and service disruption. This affects all Fedify applications that process external HTML content.
💻 Affected Systems
- Fedify
⚠️ 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 federated server application.
Likely Case
Degraded performance and intermittent service disruptions when processing malicious HTML responses.
If Mitigated
Minimal impact with proper rate limiting, input validation, and updated versions.
🎯 Exploit Status
Exploitation requires sending malicious HTML to the document loader endpoint.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 1.6.13, 1.7.14, 1.8.15, or 1.9.2
Vendor Advisory: https://github.com/fedify-dev/fedify/releases
Restart Required: Yes
Instructions:
1. Update Fedify to version 1.6.13, 1.7.14, 1.8.15, or 1.9.2 using npm update @fedify/fedify. 2. Restart your application server. 3. Verify the fix by checking the package.json version.
🔧 Temporary Workarounds
Implement Rate Limiting
allLimit requests to the document loader endpoint to reduce impact of potential attacks.
Implement rate limiting middleware for /docloader endpoints
Input Validation
allValidate and sanitize HTML responses before processing with Fedify's document loader.
Add HTML sanitization layer before passing to Fedify
🧯 If You Can't Patch
- Implement strict rate limiting on document loader endpoints
- Deploy WAF rules to block suspicious HTML patterns
🔍 How to Verify
Check if Vulnerable:
Check package.json for Fedify version. If version is below 1.6.13, 1.7.14, 1.8.15, or 1.9.2, the system is vulnerable.Check Version:
npm list @fedify/fedifyVerify Fix Applied:
Verify Fedify version is 1.6.13, 1.7.14, 1.8.15, or 1.9.2 in package.json and monitor CPU usage during HTML processing.📡 Detection & Monitoring
Log Indicators:
- High CPU usage spikes
- Slow response times from document loader
- Multiple failed HTML parsing attempts
Network Indicators:
- Unusual HTML payloads to document loader endpoints
- High volume of requests to /docloader
SIEM Query:
source="application.logs" AND ("docloader" OR "HTML parsing") AND (cpu_usage>90 OR response_time>5000)🔗 References
- https://github.com/fedify-dev/fedify/commit/2bdcb24d7d6d5886e0214ed504b63a6dc5488779
- https://github.com/fedify-dev/fedify/commit/bf2f0783634efed2663d1b187dc55461ee1f987a
- https://github.com/fedify-dev/fedify/releases/tag/1.6.13
- https://github.com/fedify-dev/fedify/releases/tag/1.7.14
- https://github.com/fedify-dev/fedify/releases/tag/1.8.15
- https://github.com/fedify-dev/fedify/releases/tag/1.9.2
- https://github.com/fedify-dev/fedify/security/advisories/GHSA-rchf-xwx2-hm93
