Kali Linux에서 업데이트를 적절하게 얻을 수 없습니다.

내가 시도하면 apt-get update다음과 같이 말합니다.

Get:1 http://archive-3.kali.org/kali kali-rolling InRelease [30.5 kB]
Err:1 http://archive-3.kali.org/kali kali-rolling InRelease
The following signatures were invalid: EXPKEYSIG ED444FF07D8D0BF6 Kali Linux Repository <[email protected]>
Reading package lists... Done
W: GPG error: http://archive-3.kali.org/kali kali-rolling InRelease: The following signatures were invalid: EXPKEYSIG ED444FF07D8D0BF6 Kali Linux Repository <[email protected]>
E: The repository 'http://http.kali.org/kali kali-rolling InRelease' is not signed.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.

내 /etc/apt/source.list모습은 다음과 같습니다.

deb http://http.kali.org/kali kali-rolling main contrib non-free
# For source package access, uncomment the following line
# deb-src http://http.kali.org/kali kali-rolling main contrib non-free
# deb cdrom:[Debian GNU/Linux 2017.3 _Kali-rolling_ - Official Snapshot amd64 L$

#deb cdrom:[Debian GNU/Linux 2017.3 _Kali-rolling_ - Official Snapshot amd64 LI$

어떻게 해야 합니까? 감사해요!