Similar to Specter, the new “Speculative Store Bypass” vulnerability, SSB for short, allows access to sensitive information about a speculative execution mechanism of the CPU. While this may sound bad to some users at first, Intel describes the gap as moderately dangerous. For SSB or “Variant 4” different gaps are exploited, which have been closed on most systems by updates of the manufacturers. Intel will also revisit the topic and publish a corresponding option to prevent this approach for different approaches.
This additional fix for SSB is said to have already been distributed in a beta release to system vendors and OS developers. This gives you the opportunity to react to the new gap. At the same time, Intel plans to have this mitigation disabled by default to prevent potential performance degradation.
Also Google’s Project Zero and Microsoft confirmed this new variant of Specter and Meltdown. According to CNET, both companies discovered these vulnerabilities a few months ago. Google reported this already in February at Intel, AMD and ARM. However, the latter state that a large part of the processors are not affected by the problem and that additional malware is needed on the device in order to be able to use the gap.