WebTunnelSSH failed with SSL Exception in Ubuntu 20.04 x86_64

[whitewinter]

The WebTunnelSSH failed on Ubuntu 20.04:

$ WebTunnelSSH --username=$user --password=$pw --login-name=$luser https://${id}.my-devices.net
Failed to open forwarding connection: SSL Exception: error:14161044:SSL routines:state_machine:internal error 
kex_exchange_identification: read: Connection reset by peer

There is no different in the resulting error if the the SDK is build with the installer script $ curl https://raw.githubusercontent.com/my-devices/agent-installer/master/install.sh | bash or with the GNU Make script $ ./buildsdk.sh.

Start the WebTunnelCient works but connect with ssh on the forwarded port failed with the same error:

ssh -p $port $user@localhost
Failed to open forwarding connection: SSL Exception: error:14161044:SSL routines:state_machine:internal error 
kex_exchange_identification: read: Connection reset by peer

Further information:

$ cat /etc/lsb-release 
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=20.04
DISTRIB_CODENAME=focal
DISTRIB_DESCRIPTION="Ubuntu 20.04.1 LTS"

$ uname -a
Linux 5.4.0-53-generic #59-Ubuntu SMP Wed Oct 21 09:38:44 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux

$ openssl version -a
OpenSSL 1.1.1f  31 Mar 2020
built on: Mon Apr 20 11:53:50 2020 UTC
platform: debian-amd64
options:  bn(64,64) rc4(16x,int) des(int) blowfish(ptr) 
compiler: gcc -fPIC -pthread -m64 -Wa,--noexecstack -Wall -Wa,--noexecstack -g -O2 -fdebug-prefix-map=/build/openssl-P_ODHM/openssl-1.1.1f=. -fstack-protector-strong -Wformat -Werror=format-security -DOPENSSL_TLS_SECURITY_LEVEL=2 -DOPENSSL_USE_NODELETE -DL_ENDIAN -DOPENSSL_PIC -DOPENSSL_CPUID_OBJ -DOPENSSL_IA32_SSE2 -DOPENSSL_BN_ASM_MONT -DOPENSSL_BN_ASM_MONT5 -DOPENSSL_BN_ASM_GF2m -DSHA1_ASM -DSHA256_ASM -DSHA512_ASM -DKECCAK1600_ASM -DRC4_ASM -DMD5_ASM -DAESNI_ASM -DVPAES_ASM -DGHASH_ASM -DECP_NISTZ256_ASM -DX25519_ASM -DPOLY1305_ASM -DNDEBUG -Wdate-time -D_FORTIFY_SOURCE=2
OPENSSLDIR: "/usr/lib/ssl"
ENGINESDIR: "/usr/lib/x86_64-linux-gnu/engines-1.1"
Seeding source: os-specific

$ python --version
Python 2.7.18