SFTP Negotiation Failed

Question

I have a single server out of 6 that will not allow negotiation of the SFTP client. The machine is able to make a connection with Filezilla SFTP so I've ruled out firewall issues.

Any idea what any of this means? I've tried to find some references on ccger.mskif but I'm coming up blank.

Any help would be appreciated.

I've included a few relevant lines from the log file in hopes it makes sense to someone here.

INFO Sftp(1)[22] SSH: Negotiation started.
ERROR Sftp(1)[22] SSH: Negotiation failed. The type initializer for 'ccger.mskif' threw an exception.
ERROR Sftp(1)[22] Info: Rebex.Net.SshException: Negotiation failed.

---> System.TypeInitializationException: The type initializer for 'ccger.mskif' threw an exception.

---> System.TypeInitializationException: The type initializer for 'ccger.juvxs' threw an exception.

---> System.Security.VerificationException: Operation could destabilize the runtime.
at ccger.vnlqd1..ctor(IEnumerable1 factories)

Comments

Hello, which version of Rebex SFTP do you use, and on which OS and which version of .NET Framework?

---

Thanks for the reply.

Rebex.Sftp R6.2 for .NET 4.0-4.8
Windows Server 2008 R2 Standard  SP1
.NET 4.0.30319

Answer 1

It's unclear which version of .NET you use, because ".NET 4.0.30319" applies to any .NET Framework 4.x version, but this actually looks like a known bug in .NET Framework 4.5.

Microsoft used to have a hotfix for this, but unfortunately, it's no longer available.

Upgrading to a more recent version of .NET Framework should resolve the issue. The recommended version to upgrade to is .NET Framework 4.6.2, because earlier 4.5/4.6 versions will reach end-of-support as soon as next month.

Comments

Thank you very much for the recommendation.  Simply installing the update to the framework corrected the issue.