GHSA-vc89-5g3r-cmhh

### Impact

Parse Server's `readOnlyMasterKey` option allows access with master-level read privileges but is documented to deny all write operations. However, some endpoints incorrectly accept the `readOnlyMasterKey` for mutating operations. This allows a caller who only holds the `readOnlyMasterKey` to create, modify, and delete Cloud Hooks and to start Cloud Jobs, which can be used for data exfiltration.

Any Parse Server deployment that uses the `readOnlyMasterKey` option is affected. Note than an attacker needs to know the `readOnlyMasterKey` to exploit this vulnerability.

### Patches

The fix adds authorization checks, rejecting mutating requests made with the `readOnlyMasterKey`.

### Workarounds

There is no known workaround other than upgrading. If upgrading is not immediately possible, ensure the `readOnlyMasterKey` value is not shared with untrusted parties.

### Resources

- GitHub security advisory: https://github.com/parse-community/parse-server/security/advisories/GHSA-vc89-5g3r-cmhh - Fixed in Parse Server 9.4.1-alpha.3: https://github.com/parse-community/parse-server/releases/tag/9.4.1-alpha.3 - Fixed in Parse Server 8.6.4: https://github.com/parse-community/parse-server/releases/tag/8.6.4