Knowledge Base
Created
Modified
Modified
The message received was unexpected or badly formatted
Problem
The message received was unexpected or badly formatted.
HRESULT error: SEC_E_ILLEGAL_MESSAGE (0x80090326)
Cause
This error happens during the TLS protocol negotiation with the server.
Possible causes:
- The server only supports an insecure protocol (SSL 3.0)
- The server uses TLS 1.2 but only supports insecure cipher suites. E.g. DHE-RSA-AES256-SHA256 (Uses DH 1024-bit key exchange. See Logjam attack).
- The server uses a ECDSA certificate with a secp521r1 curve. Schannel on Windows 10 no longer supports secp521r1.
For example, older versions of glftpd have generated a default certificate with this curve.
Solution
- For cause 1 and 2
Contact the server administrator and request an upgrade of the server software.
Enable weak and insecure ciphers on your system. We strongly recommend against this option. - For cause 3
Generate a new certificate on the server using a curve different than secp521r1. E.g. secp384r1, secp256r1 or x25519.
Keywords
TLS
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