SSH from RHEL 9 to RHEL 6 systems or 3rd party application services does not work due to SHA1 being disabled

Solution Verified - Updated -


  • Trying to open a SSH session from Red Hat Enterprise Linux 9 (RHEL 9) client to Red Hat Enterprise Linux 6 (RHEL 6) OpenSSH server fails with the following error message:

    ssh_dispatch_run_fatal: Connection to port 22: error in libcrypto
  • I use a 3rd party application service not providing strong algorithms but only SHA1-based algorithms, for example 3rd party GitBlit


  • Source system running Red Hat Enterprise Linux 9

    • DEFAULT crypto policy
  • Target system running Red Hat Enterprise Linux 6

    • openssh-server-5.3p1-124.el6_10.x86_64
  • Target service running a 3rd party application services

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