Meltdown and Spectre are not GoAnywhere specific issues. These vulnerabilities impact CPU hardware implementations.
Below are the recommendations:
1. Apply operating system updates and patches from your OS vendor, after appropriate testing and review.
2. Make necessary configuration changes to enable protection.
3. Apply an applicable firmware update from the OEM device manufacturer.
For more information see US Cert's Meltdown and Spectre Side-Channel Vulnerability Guidance - https://www.us-cert.gov/ncas/alerts/TA18-004A