I'm running Ubuntu 18.04, and I have the following linux-image and intel-microcode packages:
ii linux-image-4.18.0-17-generic 4.18.0-17.18~18.04.1 amd64 Signed kernel image generic
ii intel-microcode 3.20180807a.0ubuntu0.18.04.1 amd64 Processor microcode firmware for Intel CPUs
Assume the image is immutable, so I can't install and run the speed47 script or install additional packages—I will make a new image if this one is vulnerable.
What canonical (but not necessarily Canonical) sites can I visit to determine whether the packages contain the necessary mitigations? I'm having trouble finding this information. For example, https://wiki.ubuntu.com/SecurityTeam/KnowledgeBase/L1TF only points to information for up to 4.15, not the 4.18 kernel I have.