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Protocol Downgrade Detector

Detect SSL/TLS protocol downgrade risks

About Protocol Downgrade Detector

Our free Protocol Downgrade Detector checks your TLS server for downgrade attack vulnerabilities including POODLE, TLS_FALLBACK_SCSV bypass, and version rollback attacks. Ensures your server enforces minimum TLS version requirements and is protected against downgrade attempts.

How to Use

  1. Enter the domain name of the server to test for downgrade vulnerabilities
  2. Click "Run" to perform the protocol downgrade detection scan
  3. Review results to identify any downgrade attack vectors

Use Cases

  • •Downgrade attack prevention for critical web services
  • •PCI DSS compliance verification for TLS configuration
  • •Security hardening of legacy servers still supporting older protocols

Frequently Asked Questions

A protocol downgrade attack forces a TLS connection to use a weaker, earlier version of the protocol that has known vulnerabilities. Attackers intercept the initial handshake and trick both client and server into negotiating the lowest common protocol version.
TLS_FALLBACK_SCSV is a signaling cipher suite value that tells the server the client attempted a higher protocol version but fell back. If the server receives this signal but could have supported the higher version, it aborts the connection, preventing downgrade attacks.
POODLE (Padding Oracle On Downgraded Legacy Encryption) is a man-in-the-middle attack that exploits SSL 3.0's weak CBC cipher padding. The fix is to completely disable SSL 3.0 on your server, which no modern browser or client requires.

Tips & Best Practices

  • •Test protocol downgrade attack resistance on your servers
  • •Enable TLS_FALLBACK_SCSV for downgrade protection
  • •Disable deprecated protocols to prevent downgrade attacks
  • •Monitor for downgrade attack attempts in server logs

Technical Details

Attack: Protocol downgrade attack detection and prevention
Protection: TLS_FALLBACK_SCSV and protocol configuration
Testing: Downgrade attack simulation
Output: Downgrade protection status and recommendations

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