base64: invalid input error when trying to decode contents of yaml file

>**What specific syntax must be changed in the bash below to successfully decode the base64 encoded value which is throwing the error below?** **THE ERROR:** The following 3 simple commands are typed into the terminal of a RHEL 8 vm running in Azure: [user@myVM ~]$ myVar=$(az keyvault secret show --name "secretName" --vault-name "vaultName" --query "value") [user@myVM ~]$ echo $myVar "very.long.base64.encoded.string.representing.the.original.yaml" [user@myVM ~]$ echo $myVar | base64 --decode base64: invalid input The second command prints what looks like valid base64 encoding of a long string, perhaps a few hundred characters or more encoded. The error base64: invalid input seems to indicate that the base64 program is not able to accept the encoded input into its decode command. **THE SOURCE DATA:** The contents of the base64 encoded data above originated in a yaml file with perhaps 20 lines, which was passed through [terraform's fileBase64() command](https://www.terraform.io/language/functions/filebase64) as follows before the VM was created: resource "azurerm_key_vault_secret" "secretName" { name = "secretName" value = filebase64(var.keySourceFile) key_vault_id = azurerm_key_vault.vaultName.id } **RESULTS OF TRYING USER SUGGESTIONS:** Per @roaima suggestion, we tried the following: [user@myVM ~]$ az keyvault secret show --name "secretName" --vault-name "vaultName" --query "value" "very.long.base64.encoded.string.representing.the.original.yaml==" [user@myVM ~]$ myVar=$(az keyvault secret show --name "secretName" --vault-name "vaultName" --query "value") [user@myVM ~]$ echo "$myVar" | base64 --decode >/dev/null base64: invalid input As you can see, we validated that a long encoded string is presented by the raw command before we put it into myVar . Note that it ends with == and is surrounded by double-quotes. The raw data in the original source file that was sent into terraform looks something like: secret1: value1 secret2: value2 ... secretN: valueN Then we tried the following but you can see nothing was returned: [user@myVM ~]$ printf '%s\n' "$myVar" | base64 --decode --ignore-garbage >/dev/null [user@myVM ~]$