I know @Ejegg was getting this last night too (or at least, very similar errors)...
```
13:25:50 ++ /usr/bin/env
13:25:51 [7.7MB/0.02s] > ComposerHookHandler::onPreUpdate
13:25:51 [7.8MB/0.02s] Loading composer repositories with package information
13:25:51 [8.1MB/0.13s] Updating dependencies (including require-dev)
13:26:03 [312.5MB/11.73s] Package operations: 56 installs, 5 updates, 3 removals
13:26:03 [312.5MB/11.73s] - Removing wikimedia/ip-utils (1.0.0)
13:26:03 [312.5MB/11.75s] - Removing jakobo/hotp-php (v1.0.1)
13:26:03 [312.5MB/11.78s] - Removing christian-riesen/base32 (1.3.2)
13:26:03 [312.5MB/11.81s] - Updating ralouphie/getallheaders (2.0.5 => 3.0.3): [312.5MB/11.84s] Downloading
13:26:03
13:26:03 [Composer\Downloader\TransportException]
13:26:03 Could not authenticate against github.com
13:26:03
```