🛠️ Fixing the Kali Linux “Missing Key” APT Repository Error (2025)
If you recently tried running sudo apt update on Kali Linux and were greeted with a scary error like this:
Missing key 827C8569F2518CC677FECA1AED65462EC8D5E4C5, which is needed to verify signature.
You’re not alone — and it’s not your fault. Kali Linux maintainers recently rotated their repository signing key, and that broke package updates for everyone who hadn’t yet received the new key.
In this post, I’ll break down:
- ❓ What the issue is
- 🔒 Why it happened
- 🧩 How to fix it (with a script)
- 💡 Good practices for key verification
❓ What’s the Error?
When you run apt update, Kali attempts to validate the signature of the repository index file. If the signing key is missing or expired, you’ll see something like this:
OpenPGP signature verification failed:
Missing key 827C8569F2518CC677FECA1AED65462EC8D5E4C5
APT uses GPG keys to ensure that the packages you download are authentic and unaltered. If that verification fails, updates are blocked.
🔒 Why Did This Happen?
The Kali Linux team officially announced that they had to roll over to a new signing key for security reasons. This wasn’t a compromise — they simply lost access to the old key and decided to switch to a new one:
“We lost access to the signing key of the repository, so we had to create a new one. […] If the key was compromised, we would have revoked it.”
As of Kali 2025.1c, all new ISOs include the updated keyring. But if you’re running an older system, you’ll need to fix it manually.
🧩 How to Fix It
You can fix the problem in seconds using the following command:
sudo wget https://archive.kali.org/archive-keyring.gpg -O /usr/share/keyrings/kali-archive-keyring.gpg
Alternatively, here’s a fully automated Bash script that:
- Verifies you’re running as root
- Downloads the new key
- Validates its checksum
- Verifies its GPG contents
- Runs
apt update
🔐 Verifying the Key
Before trusting any key, you should verify its fingerprint manually. The new key’s fingerprint is:
827C 8569 F251 8CC6 77FE CA1A ED65 462E C8D5 E4C5
You can also look it up here: 🔗 https://keyserver.ubuntu.com/pks/lookup?search=827C8569F2518CC677FECA1AED65462EC8D5E4C5&fingerprint=on&op=index
Auto-Mated Fix
NOTE: You need to run this with sudo priviledges
curl -fsSL https://raw.githubusercontent.com/its-ashu-otf/Kali-Enhance/main/fix-kali-apt-key.sh | sudo bash
💡 Pro Tips
- Always check the SHA1/256 hash of keyring files you manually download.
- Prefer downloading from
https://archive.kali.org/instead of mirrors. - Use
gpg --keyringto inspect key contents before trusting them. - Consider switching to newer Kali ISOs (
2025.1cor later) if you’re doing a fresh install.
🧰 Got stuck? You can find help on the Kali Forums , Discord , or IRC .