no matching host key type found. Their offer: ssh-dss {#no-matching-host-key-type-found-their-offer-ssh-dss}

使用SSH登录时报错如下：

|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | 1

    Unable to negotiate with 20.1.1.174 port 22: no matching host key type found. Their offer: ssh-dss    

报错原因是OpenSSH7.0之后不再支持 ssh-dss 算法，可以通过添加参数 -oHostKeyAlgorithms=+ssh-dss 来支持该算法：

|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | 1

    sftp -oHostKeyAlgorithms=+ssh-dss -i id_rsa test@20.1.1.174    

Permissions 0644 for 'id_rsa' are too open {#permissions-0644-for-id_rsa-are-too-open}

使用SSH登录时报错如下：

|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | 1 2 3

    Permissions 0644 for 'id_rsa' are too open.     It is required that your private key files are NOT accessible by others.     This private key will be ignored.    

这个报错是因为 id_rsa 是私钥文件，属于敏感文件，不能开放权限给其他用户组，哪怕是只读也不行，在缩小权限之前该私钥文件将一直被忽略。

通过赋予该文件400或600的权限即可成功登陆SSH：

|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------| | 1 2

    chmod 400 id_rsa     chmod 600 id_rsa    

参考链接 {#参考链接}

• no matching host key type found. Their offer: ssh-dss,ssh-rsa
• 【web渗透】私钥ssh远程登录报错：permission 0644 for 'id_rsa' are too open