https://aws.amazon.com/security/security-bulletins/AWS-2019-004/
According to Amazon advisory, fixes have been applied and "no customer action is required at the Infrastructure level". Reading from other sources [1], I can only conclude that Amazon has not provided the knobs needed to do the mitigation. This explains the issue for MDS and TAA. SSB is likely vulnerable for the same reasons, but I'll look for their advisory and update it here. Same thing for ITLB multihit. One possible avenue of investigation is verifying if VERW is being used and providing the mitigation for the MDS case. Regards. Cascardo. [1] https://www.reddit.com/r/aws/comments/br38fl/sidechannel_md_clear_cpu_flags_not_being_passed/ -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-aws in Ubuntu. https://bugs.launchpad.net/bugs/1891812 Title: Missing Linux Kernel Mitigations Status in linux-aws package in Ubuntu: New Bug description: We need assistance in resolving OpenVAS security scan findings related to Spectre/Meltdown vulnerabilities across both Ubuntu 16.04LTS/20.04LTS platforms on AWS. Both the systems were updated with the latest supported Kernel versions (4.4.0.1111-aws & 5.4.0-1021-aws), relevant Intel Microcode updates (3.20200609.0ubuntu0.20.04.2) and suggested mitigations on the Ubuntu Site. Please reference the findings below and suggest any mitigations that we may need to take to address them. The Linux Kernel on the remote host is missing one or more mitigation(s) for hardware vulnerabilities as reported by the sysfs interface: sysfs file (Related CVE(s)) | Kernel status -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- /sys/devices/system/cpu/vulnerabilities/itlb_multihit (CVE-2018-12207) | KVM: Vulnerable /sys/devices/system/cpu/vulnerabilities/mds (CVE-2018-12126, CVE-2018-12130, CVE-2018-12127, CVE-2019-11091) | Vulnerable: Clear CPU buffers attempted, no microcode; SMT Host state unknown /sys/devices/system/cpu/vulnerabilities/spec_store_bypass (CVE-2018-3639) | Vulnerable Notes on specific Kernel status output: - sysfs file missing: The sysfs interface is available but the sysfs file for this specific vulnerability is missing. This means the kernel doesn't know this vulnerability yet and is not providing any mitigation which means the target system is vulnerable. - Strings including "Mitigation:", "Not affected" or "Vulnerable" are reported directly by the Linux Kernel. - All other strings are responses to various SSH commands. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-aws/+bug/1891812/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp