Git "fatal: Could not read from remote repository" in CI

Git connected far enough to talk to the remote but was refused or could not find the repository. The trailing hint - "make sure you have the correct access rights and the repository exists" - points at access or a wrong URL, not a network outage.

What this error means

A git clone or git fetch aborts with fatal: Could not read from remote repository and the standard hint about access rights. It is deterministic for a given URL and credential - it fails the same way on every retry.

git clone output

git@github.com: Permission denied (publickey).
fatal: Could not read from remote repository.

Please make sure you have the correct access rights
and the repository exists.

Common causes

Missing or wrong credentials

The most common case in CI: SSH has no usable key, or the token/credential helper supplies nothing valid, so the remote refuses the connection before any repository data is read.

Wrong remote URL or repository does not exist

A typo in the org/repo name, a renamed or deleted repository, or pointing at a private repo the runner cannot see all surface as the same generic error.

The account lacks access to a private repository

The credential is valid but the identity behind it (a deploy key, a GitHub App token, a PAT) was never granted access to this specific repository.

How to fix it

Confirm the URL and that the repo is reachable

Print the configured remote and try a non-mutating probe with the same credentials the job uses.

Terminal

git remote -v
git ls-remote https://github.com/org/repo.git   # lists refs if access is OK

Provide working credentials for the clone

For SSH, ensure a deploy key or the runner key is loaded and added to the repo/org.
For HTTPS, supply a token via the credential helper or an x-access-token URL.
On GitHub Actions, confirm actions/checkout has access - for other repos add a PAT or deploy key via the token/ssh-key input.

How to prevent it

Use actions/checkout (or the equivalent) with an explicit token for cross-repo clones.
Grant deploy keys / App installations access to every repo a job clones.
Pin the exact remote URL in the workflow instead of relying on inherited config.