https://www.theregister.co.uk/2018/02/14/meltdown_spectre_exploit_variants/

When details of the Meltdown and Spectre CPU security vulnerabilities emerged last month, the researchers involved hinted that further exploits may be developed beyond the early proof-of-concept examples.

It didn't take long. In a research paper – "MeltdownPrime and SpectrePrime: Automatically-Synthesized Attacks Exploiting Invalidation-Based Coherence Protocols" – out this month, bit boffins from Princeton University and chip designer Nvidia describe variants of Meltdown and Spectre exploit code that can be used to conduct side-channel timing attacks.