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add more legacy ssh ciphers #1103

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add more legacy ssh ciphers #1103

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12 changes: 8 additions & 4 deletions hydra-ssh.c
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Original file line number Diff line number Diff line change
Expand Up @@ -48,9 +48,11 @@ int32_t start_ssh(int32_t s, char *ip, int32_t port, unsigned char options, char
ssh_options_set(session, SSH_OPTIONS_TIMEOUT, &hydra_options.waittime);
ssh_options_set(session, SSH_OPTIONS_COMPRESSION_C_S, "none");
ssh_options_set(session, SSH_OPTIONS_COMPRESSION_S_C, "none");
// might be better to add the legacy (first two for KEX and HOST) to the default instead of specifying the full list
ssh_options_set(session, SSH_OPTIONS_KEY_EXCHANGE, "diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,curve25519-sha256,curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group18-sha512,diffie-hellman-group16-sha512,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha256");
// might be better to add the legacy to the default instead of specifying the full list
ssh_options_set(session, SSH_OPTIONS_KEY_EXCHANGE, "diffie-hellman-group1-sha1,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,curve25519-sha256,curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group18-sha512,diffie-hellman-group16-sha512,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha256");
ssh_options_set(session, SSH_OPTIONS_HOSTKEYS, "ssh-rsa,ssh-dss,ssh-ed25519,ecdsa-sha2-nistp521,ecdsa-sha2-nistp384,ecdsa-sha2-nistp256,sk-ssh-ed25519@openssh.com,sk-ecdsa-sha2-nistp256@openssh.com,rsa-sha2-512,rsa-sha2-256");
ssh_options_set(session, SSH_OPTIONS_HMAC_C_S, "hmac-sha1,hmac-sha1-96,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha2-256,hmac-sha2-512");
ssh_options_set(session, SSH_OPTIONS_HMAC_S_C, "hmac-sha1,hmac-sha1-96,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha2-256,hmac-sha2-512");

@vanhauser-thc vanhauser-thc Jul 28, 2026

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duplicate line

if (ssh_connect(session) != 0) {
// if the connection was drop, exit and let hydra main handle it
if (verbose)
Expand Down Expand Up @@ -214,9 +216,11 @@ int32_t service_ssh_init(char *ip, int32_t sp, unsigned char options, char *misc
ssh_options_set(session, SSH_OPTIONS_TIMEOUT, &hydra_options.waittime);
ssh_options_set(session, SSH_OPTIONS_COMPRESSION_C_S, "none");
ssh_options_set(session, SSH_OPTIONS_COMPRESSION_S_C, "none");
// might be better to add the legacy (first two for KEX and HOST) to the default instead of specifying the full list
ssh_options_set(session, SSH_OPTIONS_KEY_EXCHANGE, "diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,curve25519-sha256,curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group18-sha512,diffie-hellman-group16-sha512,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha256");
// might be better to add the legacy to the default instead of specifying the full list
ssh_options_set(session, SSH_OPTIONS_KEY_EXCHANGE, "diffie-hellman-group1-sha1,diffie-hellman-group-exchange-sha1,diffie-hellman-group14-sha1,curve25519-sha256,curve25519-sha256@libssh.org,ecdh-sha2-nistp256,ecdh-sha2-nistp384,ecdh-sha2-nistp521,diffie-hellman-group18-sha512,diffie-hellman-group16-sha512,diffie-hellman-group-exchange-sha256,diffie-hellman-group14-sha256");
ssh_options_set(session, SSH_OPTIONS_HOSTKEYS, "ssh-rsa,ssh-dss,ssh-ed25519,ecdsa-sha2-nistp521,ecdsa-sha2-nistp384,ecdsa-sha2-nistp256,sk-ssh-ed25519@openssh.com,sk-ecdsa-sha2-nistp256@openssh.com,rsa-sha2-512,rsa-sha2-256");
ssh_options_set(session, SSH_OPTIONS_HMAC_C_S, "hmac-sha1,hmac-sha1-96,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha2-256,hmac-sha2-512");
ssh_options_set(session, SSH_OPTIONS_HMAC_S_C, "hmac-sha1,hmac-sha1-96,hmac-sha2-256-etm@openssh.com,hmac-sha2-512-etm@openssh.com,hmac-sha2-256,hmac-sha2-512");

@vanhauser-thc vanhauser-thc Jul 28, 2026

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Duplicate line

@tothi tothi Jul 28, 2026

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sorry, I don't understand. which one is duplicate?

@vanhauser-thc vanhauser-thc Jul 28, 2026

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This is the same line like the one above

if (ssh_connect(session) != 0) {
fprintf(stderr, "[ERROR] could not connect to ssh://%s:%d - %s\n", hydra_address2string_beautiful(ip), port, ssh_get_error(session));
return 2;
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