438
SIP
438 Invalid Identity Header
The server obtained the certificate from the Identity-Info header but the signature in the Identity header is invalid.
When You See This Code
When the cryptographic signature in the Identity header does not match the message content, indicating possible tampering.
How to Fix
Regenerate the Identity header with a correct signature. Ensure no intermediary is modifying signed headers after signing.
Specification
Compare With
Guides
401 Unauthorized vs 403 Forbidden: When to Use Each
Security & Authentication
SIP Response Codes: Understanding VoIP Call Flow
Real-Time Protocols
SIP Call Flow: Understanding Session Setup
Real-Time Protocols
WebRTC Signaling with SIP and WebSocket
Real-Time Protocols
RFC 3261: SIP Protocol Deep Dive
Protocol Deep Dives
TLS 1.3: Faster, Simpler, More Secure
Protocol Deep Dives
Glossary
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Request Method (HTTP Verb)
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TLS Versions