This can happen from time to time when the local Cocoapods repo gets stale containing older specs. You can do the following to just remove the local repo of specs:
sudo rm -fr ~/.cocoapods/repos/master
As of CocoaPods 1.0, you will then get this error if you try to run your project:
You have either:
* out-of-date source repos which you can update with `pod repo update`.
* mistyped the name or version.
* not added the source repo that hosts the Podspec to your Podfile.
Note: as of CocoaPods 1.0, `pod repo update` does not happen on `pod install` by default.
Processing node_modules failed. Error: Command pod failed with exit code 1
As mentioned, just run:
pod repo update
And then you will be all set.