Hello Coltoper,
HPE 5120 (JE068A) is Comware5 device, There is no way to configure SSH algorithoms in Comware5.
What you can do is, Configfure SSH server ACL to block unsolicited or unwanted SSH login .
Create ACL
[HPE]acl number 2000
[HPE-acl-basic-2000]rule 0 permit source <source IP/network> <Wildcard mask>
[[HPE-acl-basic-2000]quit
Apply ACL for SSH
[HPE]user-interface vty 0 4
[HPE-ui-vty0-4]acl 2000 inbound
[HPE-ui-vty0-4]quit
Eventually H/W upgrade will be the go-forward plan.
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Thank you
Santanu
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