CVE-2021-27702
📋 TL;DR
This vulnerability allows attackers to bypass authentication via the diagnostic utility in the Sercomm Router Etisalat Model S3-AC2100 dashboard. It enables unauthorized access to router functions and potentially sensitive information. Only users of this specific router model are affected.
💻 Affected Systems
- Sercomm Router Etisalat Model S3-AC2100
⚠️ 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 router compromise allowing attacker to intercept all network traffic, modify router settings, install malware, and pivot to internal network devices.
Likely Case
Unauthorized access to router configuration, network information disclosure, and potential denial of service through configuration changes.
If Mitigated
Limited impact if router is behind additional firewalls and network segmentation prevents lateral movement from compromised router.
🎯 Exploit Status
The vulnerability is in the diagnostic utility which may be accessible without proper authentication. Public GitHub repository contains details.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: Unknown
Vendor Advisory: No official vendor advisory found
Restart Required: No
Instructions:
Check with Etisalat or Sercomm for firmware updates. If available, download latest firmware from official sources and apply through router admin interface.
🔧 Temporary Workarounds
Disable diagnostic utility
allTurn off diagnostic features in router settings if possible
Change default credentials
allEnsure strong, unique admin passwords are set
🧯 If You Can't Patch
- Replace affected router with different model
- Place router behind additional firewall with strict access controls
🔍 How to Verify
Check if Vulnerable:
Attempt to access diagnostic utility without authentication via router dashboard. Check if unauthorized access to diagnostic features is possible.Check Version:
Check router admin interface for firmware version informationVerify Fix Applied:
Test if diagnostic utility now requires proper authentication. Verify firmware version matches patched version if available.📡 Detection & Monitoring
Log Indicators:
- Unauthorized access attempts to diagnostic pages
- Multiple failed login attempts followed by diagnostic access
Network Indicators:
- Unusual traffic patterns from router
- External connections to router diagnostic ports
SIEM Query:
source_ip="router_ip" AND (url_path="*diagnostic*" OR url_path="*utility*") AND user="anonymous"