How do I use the right cipher with pscp.exe?

Question

I have been using pscp to upload some files to a remote server but apparently they are updating the security so that only certain SFTP and MAC ciphers are allowed, but I'm not really a programmer so I don't know what this all entails.

Right now I have this command in a batch script (using generic capital letters here instead of the actual words/strings used):

echo y | "CURRENT_PATH\pscp.exe" -sftp -P 22 -pw "PASSWORD" "LOCAL\PATH\TO\FILE.txt" SOME_SERVER@SERVER.COM:/SERVER/PATH/TO/FILE.txt

How do I change or update this so it is compatible with the following:

Allowed SSH Ciphers: aes256-cbc, aes256-ctr

Allowed MAC Ciphers: hmac-sha2-512, hmac-sha2-256

I don't know if I need only one or both of these SSH/MAC things to make it work.

This question would better fit to [su]. – Martin Prikryl Mar 19 '19 at 07:21 — Martin Prikryl, Mar 19 '19 at 07:21

score 1 · Accepted Answer · answered Mar 19 '19 at 07:25

PSCP (as any SSH client) will automatically pick the best algorithms out of those mutually supported by it and the server. There's nothing you should do.

If PSCP supports any algorithm out of those supported/allowed by the server, it will use them automatically.

If not, no configuration will fix it (except a rare case, when the best such algorithm is actually considered insecure by PSCP/PuTTY – what is not your case). All you can do, if it does not work, is to make sure you have the latest version of PSCP/PuTTY.

Obligatory warning: Never use echo y as an automated response to a pcp hostkey prompt.

How do I use the right cipher with pscp.exe?

1 Answers1