[    0.830433] MDS CPU bug present and SMT on, data leak possible. See https://www.kernel.org/doc/html/latest/admin-guide/hw-vuln/mds.html for more details.

Kernel is Linux 5.4.0-125-generic #141-Ubuntu SMP Wed Aug 10 13:42:03 UTC 2022 x86_64
CPU is Intel(R) Xeon(R) CPU           E5620  @ 2.40GHz

scpej-hga [~] # spectre-meltdown-checker --explain
Spectre and Meltdown mitigation detection tool v0.43

Checking for vulnerabilities on current system
Kernel is Linux 5.4.0-125-generic #141-Ubuntu SMP Wed Aug 10 13:42:03 UTC 2022 x86_64
CPU is Intel(R) Xeon(R) CPU           E5620  @ 2.40GHz

Hardware check
* Hardware support (CPU microcode) for mitigation techniques
  * Indirect Branch Restricted Speculation (IBRS)
    * SPEC_CTRL MSR is available:  YES 
    * CPU indicates IBRS capability:  YES  (SPEC_CTRL feature bit)
  * Indirect Branch Prediction Barrier (IBPB)
    * PRED_CMD MSR is available:  YES 
    * CPU indicates IBPB capability:  YES  (SPEC_CTRL feature bit)
  * Single Thread Indirect Branch Predictors (STIBP)
    * SPEC_CTRL MSR is available:  YES 
    * CPU indicates STIBP capability:  YES  (Intel STIBP feature bit)
  * Speculative Store Bypass Disable (SSBD)
    * CPU indicates SSBD capability:  YES  (Intel SSBD)
  * L1 data cache invalidation
    * FLUSH_CMD MSR is available:  YES 
    * CPU indicates L1D flush capability:  YES  (L1D flush feature bit)
  * Microarchitectural Data Sampling
    * VERW instruction is available:  NO 
  * Enhanced IBRS (IBRS_ALL)
    * CPU indicates ARCH_CAPABILITIES MSR availability:  NO 
    * ARCH_CAPABILITIES MSR advertises IBRS_ALL capability:  NO 
  * CPU explicitly indicates not being vulnerable to Meltdown/L1TF (RDCL_NO):  NO 
  * CPU explicitly indicates not being vulnerable to Variant 4 (SSB_NO):  NO 
  * CPU/Hypervisor indicates L1D flushing is not necessary on this system:  NO 
  * Hypervisor indicates host CPU might be vulnerable to RSB underflow (RSBA):  NO 
  * CPU explicitly indicates not being vulnerable to Microarchitectural Data Sampling (MDS_NO):  NO 
  * CPU explicitly indicates not being vulnerable to TSX Asynchronous Abort (TAA_NO):  NO 
  * CPU explicitly indicates not being vulnerable to iTLB Multihit (PSCHANGE_MSC_NO):  NO 
  * CPU explicitly indicates having MSR for TSX control (TSX_CTRL_MSR):  NO 
  * CPU supports Transactional Synchronization Extensions (TSX):  NO 
  * CPU supports Software Guard Extensions (SGX):  NO 
  * CPU microcode is known to cause stability problems:  NO  (model 0x2c family 0x6 stepping 0x2 ucode 0x1f cpuid 0x206c2)
  * CPU microcode is the latest known available version:  YES  (latest version is 0x1f dated 2018/05/08 according to builtin firmwares DB v130.20191104+i20191027)
* CPU vulnerability to the speculative execution attack variants
  * Vulnerable to CVE-2017-5753 (Spectre Variant 1, bounds check bypass):  YES 
  * Vulnerable to CVE-2017-5715 (Spectre Variant 2, branch target injection):  YES 
  * Vulnerable to CVE-2017-5754 (Variant 3, Meltdown, rogue data cache load):  YES 
  * Vulnerable to CVE-2018-3640 (Variant 3a, rogue system register read):  YES 
  * Vulnerable to CVE-2018-3639 (Variant 4, speculative store bypass):  YES 
  * Vulnerable to CVE-2018-3615 (Foreshadow (SGX), L1 terminal fault):  NO 
  * Vulnerable to CVE-2018-3620 (Foreshadow-NG (OS), L1 terminal fault):  YES 
  * Vulnerable to CVE-2018-3646 (Foreshadow-NG (VMM), L1 terminal fault):  YES 
  * Vulnerable to CVE-2018-12126 (Fallout, microarchitectural store buffer data sampling (MSBDS)):  YES 
  * Vulnerable to CVE-2018-12130 (ZombieLoad, microarchitectural fill buffer data sampling (MFBDS)):  YES 
  * Vulnerable to CVE-2018-12127 (RIDL, microarchitectural load port data sampling (MLPDS)):  YES 
  * Vulnerable to CVE-2019-11091 (RIDL, microarchitectural data sampling uncacheable memory (MDSUM)):  YES 
  * Vulnerable to CVE-2019-11135 (ZombieLoad V2, TSX Asynchronous Abort (TAA)):  NO 
  * Vulnerable to CVE-2018-12207 (No eXcuses, iTLB Multihit, machine check exception on page size changes (MCEPSC)):  YES 

CVE-2017-5753 aka 'Spectre Variant 1, bounds check bypass'
* Mitigated according to the /sys interface:  YES  (Mitigation: usercopy/swapgs barriers and __user pointer sanitization)
* Kernel has array_index_mask_nospec:  YES  (1 occurrence(s) found of x86 64 bits array_index_mask_nospec())
* Kernel has the Red Hat/Ubuntu patch:  NO 
* Kernel has mask_nospec64 (arm64):  NO 
> STATUS:  NOT VULNERABLE  (Mitigation: usercopy/swapgs barriers and __user pointer sanitization)

CVE-2017-5715 aka 'Spectre Variant 2, branch target injection'
* Mitigated according to the /sys interface:  YES  (Mitigation: Retpolines, IBPB: conditional, IBRS_FW, STIBP: conditional, RSB filling)
* Mitigation 1
  * Kernel is compiled with IBRS support:  YES 
    * IBRS enabled and active:  YES  (for firmware code only)
  * Kernel is compiled with IBPB support:  YES 
    * IBPB enabled and active:  YES 
* Mitigation 2
  * Kernel has branch predictor hardening (arm):  NO 
  * Kernel compiled with retpoline option:  YES 
> STATUS:  VULNERABLE  (IBRS+IBPB or retpoline+IBPB is needed to mitigate the vulnerability)

> How to fix: To mitigate this vulnerability, you need either IBRS + IBPB, both requiring hardware support from your CPU microcode in addition to kernel support, or a kernel compiled with retpoline and IBPB, with retpoline requiring a retpoline-aware compiler (re-run this script with -v to know if your version of gcc is retpoline-aware) and IBPB requiring hardware support from your CPU microcode. The retpoline + IBPB approach is generally preferred as the performance impact is lower. More information about how to enable the missing bits for those two possible mitigations on your system follow. You only need to take one of the two approaches.

> How to fix: Both your CPU and your kernel have IBRS support, but it is currently disabled. You may enable it. Check in your distro's documentation on how to do this.

CVE-2017-5754 aka 'Variant 3, Meltdown, rogue data cache load'
* Mitigated according to the /sys interface:  YES  (Mitigation: PTI)
* Kernel supports Page Table Isolation (PTI):  YES 
  * PTI enabled and active:  YES 
  * Reduced performance impact of PTI:  YES  (CPU supports PCID, performance impact of PTI will be reduced)
* Running as a Xen PV DomU:  NO 
> STATUS:  NOT VULNERABLE  (Mitigation: PTI)

CVE-2018-3640 aka 'Variant 3a, rogue system register read'
* CPU microcode mitigates the vulnerability:  YES 
> STATUS:  NOT VULNERABLE  (your CPU microcode mitigates the vulnerability)

CVE-2018-3639 aka 'Variant 4, speculative store bypass'
* Mitigated according to the /sys interface:  YES  (Mitigation: Speculative Store Bypass disabled via prctl and seccomp)
* Kernel supports disabling speculative store bypass (SSB):  YES  (found in /proc/self/status)
* SSB mitigation is enabled and active:  YES  (per-thread through prctl)
* SSB mitigation currently active for selected processes:  YES  (anvil auth config dovecot haveged imap imap-login irqbalance log stats systemd-journald systemd-logind systemd-networkd systemd-resolved systemd-timesyncd systemd-udevd)
> STATUS:  NOT VULNERABLE  (Mitigation: Speculative Store Bypass disabled via prctl and seccomp)

CVE-2018-3615 aka 'Foreshadow (SGX), L1 terminal fault'
* CPU microcode mitigates the vulnerability:  N/A 
> STATUS:  NOT VULNERABLE  (your CPU vendor reported your CPU model as not vulnerable)

CVE-2018-3620 aka 'Foreshadow-NG (OS), L1 terminal fault'
* Mitigated according to the /sys interface:  YES  (Mitigation: PTE Inversion)
* Kernel supports PTE inversion:  YES  (found in kernel image)
* PTE inversion enabled and active:  YES 
> STATUS:  NOT VULNERABLE  (Mitigation: PTE Inversion)

CVE-2018-3646 aka 'Foreshadow-NG (VMM), L1 terminal fault'
* Information from the /sys interface: Mitigation: PTE Inversion
* This system is a host running a hypervisor:  NO 
* Mitigation 1 (KVM)
  * EPT is disabled:  N/A  (the kvm_intel module is not loaded)
* Mitigation 2
  * L1D flush is supported by kernel:  YES  (found flush_l1d in /proc/cpuinfo)
  * L1D flush enabled:  UNKNOWN  (unrecognized mode)
  * Hardware-backed L1D flush supported:  YES  (performance impact of the mitigation will be greatly reduced)
  * Hyper-Threading (SMT) is enabled:  YES 
> STATUS:  NOT VULNERABLE  (this system is not running a hypervisor)

CVE-2018-12126 aka 'Fallout, microarchitectural store buffer data sampling (MSBDS)'
* Mitigated according to the /sys interface:  NO  (Vulnerable: Clear CPU buffers attempted, no microcode; SMT vulnerable)
* Kernel supports using MD_CLEAR mitigation:  YES  (found md_clear implementation evidence in kernel image)
* Kernel mitigation is enabled and active:  NO 
* SMT is either mitigated or disabled:  NO 
> STATUS:  VULNERABLE  (Your kernel supports mitigation, but your CPU microcode also needs to be updated to mitigate the vulnerability)

CVE-2018-12130 aka 'ZombieLoad, microarchitectural fill buffer data sampling (MFBDS)'
* Mitigated according to the /sys interface:  NO  (Vulnerable: Clear CPU buffers attempted, no microcode; SMT vulnerable)
* Kernel supports using MD_CLEAR mitigation:  YES  (found md_clear implementation evidence in kernel image)
* Kernel mitigation is enabled and active:  NO 
* SMT is either mitigated or disabled:  NO 
> STATUS:  VULNERABLE  (Your kernel supports mitigation, but your CPU microcode also needs to be updated to mitigate the vulnerability)

CVE-2018-12127 aka 'RIDL, microarchitectural load port data sampling (MLPDS)'
* Mitigated according to the /sys interface:  NO  (Vulnerable: Clear CPU buffers attempted, no microcode; SMT vulnerable)
* Kernel supports using MD_CLEAR mitigation:  YES  (found md_clear implementation evidence in kernel image)
* Kernel mitigation is enabled and active:  NO 
* SMT is either mitigated or disabled:  NO 
> STATUS:  VULNERABLE  (Your kernel supports mitigation, but your CPU microcode also needs to be updated to mitigate the vulnerability)

CVE-2019-11091 aka 'RIDL, microarchitectural data sampling uncacheable memory (MDSUM)'
* Mitigated according to the /sys interface:  NO  (Vulnerable: Clear CPU buffers attempted, no microcode; SMT vulnerable)
* Kernel supports using MD_CLEAR mitigation:  YES  (found md_clear implementation evidence in kernel image)
* Kernel mitigation is enabled and active:  NO 
* SMT is either mitigated or disabled:  NO 
> STATUS:  VULNERABLE  (Your kernel supports mitigation, but your CPU microcode also needs to be updated to mitigate the vulnerability)

CVE-2019-11135 aka 'ZombieLoad V2, TSX Asynchronous Abort (TAA)'
* Mitigated according to the /sys interface:  YES  (Not affected)
* TAA mitigation is supported by kernel:  YES  (found tsx_async_abort in kernel image)
* TAA mitigation enabled and active:  NO 
> STATUS:  NOT VULNERABLE  (your CPU vendor reported your CPU model as not vulnerable)

CVE-2018-12207 aka 'No eXcuses, iTLB Multihit, machine check exception on page size changes (MCEPSC)'
* Mitigated according to the /sys interface:  UNKNOWN  (KVM: Vulnerable)
* This system is a host running a hypervisor:  NO 
* iTLB Multihit mitigation is supported by kernel:  YES  (found itlb_multihit in kernel image)
* iTLB Multihit mitigation enabled and active:  NO 
> STATUS:  NOT VULNERABLE  (this system is not running a hypervisor)

> SUMMARY: CVE-2017-5753:OK CVE-2017-5715:KO CVE-2017-5754:OK CVE-2018-3640:OK CVE-2018-3639:OK CVE-2018-3615:OK CVE-2018-3620:OK CVE-2018-3646:OK CVE-2018-12126:KO CVE-2018-12130:KO CVE-2018-12127:KO CVE-2019-11091:KO CVE-2019-11135:OK CVE-2018-12207:OK

A false sense of security is worse than no security at all, see --disclaimer

scpej-hga [~] # cat /sys/devices/system/cpu/vulnerabilities/mds
Vulnerable: Clear CPU buffers attempted, no microcode; SMT vulnerable

scpej-hga [~] # dpkg -s intel-microcode
Package: intel-microcode
Status: install ok installed
Priority: standard
Section: non-free/admin
Installed-Size: 5801
Maintainer: Ubuntu Developers <ubuntu-devel-discuss@lists.ubuntu.com>
Architecture: amd64
Version: 3.20220510.0ubuntu0.20.04.1
Depends: iucode-tool (>= 1.0)
Recommends: initramfs-tools (>= 0.113~)
Conflicts: microcode.ctl (<< 0.18~0)
Conffiles:
 /etc/default/intel-microcode 6a68a0e6e2d2ef001f1a374ece3c8558
 /etc/kernel/preinst.d/intel-microcode 4324b7d12701909b3a76bb5c6468a571
 /etc/modprobe.d/intel-microcode-blacklist.conf 71327241f6583b34944e638a955aba91
Description: Processor microcode firmware for Intel CPUs
 This package contains updated system processor microcode for
 Intel i686 and Intel X86-64 processors.  Intel releases microcode
 updates to correct processor behavior as documented in the
 respective processor specification updates.
 .
 For AMD processors, please refer to the amd64-microcode package.
Homepage: https://github.com/intel/Intel-Linux-Processor-Microcode-Data-Files
Original-Maintainer: Henrique de Moraes Holschuh <hmh@debian.org>