Linux私钥登陆提示server refused our key

背景

家庭内网装了个物理机的Ubuntu server，用的最新版本的22.04，然后用windows端的mobaxterm和navicat使用ssh私钥连接内网服务器时返回了Server refused our key的异常

问题原因

openssh 8.8开始默认禁用了使用SHA-1哈希算法的RSA签名,看了一下ubuntu server 22.04的默认openssh版本：

shell

➜  ~ ssh -V
OpenSSH_8.9p1 Ubuntu-3, OpenSSL 3.0.2 15 Mar 2022

https://www.openssh.com/txt/release-8.8
This release disables RSA signatures using the SHA-1 hash algorithm by default. This change has been made as the SHA-1 hash algorithm is cryptographically broken, and it is possible to create chosen-prefix hash collisions for <USD$50K [1]

解决方案

shell

vim /etc/ssh/sshd_config

# 添加配置
PubkeyAcceptedKeyTypes +ssh-rsa


systemctl restart sshd