解决kali更新源时出现签名无效问题

首先打开kali添加更新源

vim  /etc/apt/sources.list 

添加更新源

#中科大
deb http://mirrors.ustc.edu.cn/kali kali-rolling main non-free contrib
deb-src http://mirrors.ustc.edu.cn/kali kali-rolling main non-free contrib

#阿里云
#deb http://mirrors.aliyun.com/kali kali-rolling main non-free contrib
#deb-src http://mirrors.aliyun.com/kali kali-rolling main non-free contrib

#清华大学
#deb http://mirrors.tuna.tsinghua.edu.cn/kali kali-rolling main contrib non-free
#deb-src https://mirrors.tuna.tsinghua.edu.cn/kali kali-rolling main contrib non-free

#浙大
#deb http://mirrors.zju.edu.cn/kali kali-rolling main contrib non-free
#deb-src http://mirrors.zju.edu.cn/kali kali-rolling main contrib non-free

#东软大学
#deb http://mirrors.neusoft.edu.cn/kali kali-rolling/main non-free contrib

查看是否含有apt.conf文件，目录在/etc/apt/,我的只有apt.conf.d目录，进入该目录然后修改70debconf文件，在里面输入了Acquire::AllowInsecureRepositories “true”; 

然后执行apt-config dump，查看apt的对应配置有无生效 

Acquire::AllowInsecureRepositories的属性值由最初的”0”变成了”true” 就是配置成功

然后敲入apt-get update && apt-get upgrade

参考网址：https://blog.csdn.net/include_heqile/article/details/79275944

https://wiki.debian.org/AptConf