Spectre and Meltdown Checks
^^^^^^^^^^^^^^^^^^^^^^^^^^^

Following section displays the output of a running shell script to tell if
system is vulnerable against the several "speculative execution" CVEs that were
made public in 2018. Script is available on `Spectre & Meltdown Checker Github
<https://github.com/speed47/spectre-meltdown-checker>`_.

::

  Spectre and Meltdown mitigation detection tool v0.44+

  Checking for vulnerabilities on current system
  Kernel is Linux 4.15.0-72-generic #81-Ubuntu SMP Tue Nov 26 12:21:09 UTC 2019 aarch64
  CPU is

  Hardware check
  * CPU vulnerability to the speculative execution attack variants
    * Affected by CVE-2017-5753 (Spectre Variant 1, bounds check bypass):  YES
    * Affected by CVE-2017-5715 (Spectre Variant 2, branch target injection):  YES
    * Affected by CVE-2017-5754 (Variant 3, Meltdown, rogue data cache load):  NO
    * Affected by CVE-2018-3640 (Variant 3a, rogue system register read):  NO
    * Affected by CVE-2018-3639 (Variant 4, speculative store bypass):  YES
    * Affected by CVE-2018-3615 (Foreshadow (SGX), L1 terminal fault):  NO
    * Affected by CVE-2018-3620 (Foreshadow-NG (OS), L1 terminal fault):  NO
    * Affected by CVE-2018-3646 (Foreshadow-NG (VMM), L1 terminal fault):  NO
    * Affected by CVE-2018-12126 (Fallout, microarchitectural store buffer data sampling (MSBDS)):  NO
    * Affected by CVE-2018-12130 (ZombieLoad, microarchitectural fill buffer data sampling (MFBDS)):  NO
    * Affected by CVE-2018-12127 (RIDL, microarchitectural load port data sampling (MLPDS)):  NO
    * Affected by CVE-2019-11091 (RIDL, microarchitectural data sampling uncacheable memory (MDSUM)):  NO
    * Affected by CVE-2019-11135 (ZombieLoad V2, TSX Asynchronous Abort (TAA)):  NO
    * Affected by CVE-2018-12207 (No eXcuses, iTLB Multihit, machine check exception on page size changes (MCEPSC)):  NO
    * Affected by CVE-2020-0543 (Special Register Buffer Data Sampling (SRBDS)):  NO

  CVE-2017-5753 aka 'Spectre Variant 1, bounds check bypass'
  * Mitigated according to the /sys interface:  YES  (Mitigation: __user pointer sanitization)
  * Kernel has array_index_mask_nospec:  NO
  * Kernel has the Red Hat/Ubuntu patch:  NO
  * Kernel has mask_nospec64 (arm64):  NO
  * Kernel has array_index_nospec (arm64):  NO
  * Checking count of LFENCE instructions following a jump in kernel...  NO  (only 0 jump-then-lfence instructions found, should be >= 30 (heuristic))
  > STATUS:  NOT VULNERABLE  (Mitigation: __user pointer sanitization)

  CVE-2017-5715 aka 'Spectre Variant 2, branch target injection'
  * Mitigated according to the /sys interface:  NO  (Vulnerable)
  * Mitigation 1
    * Kernel is compiled with IBRS support:  YES
    * IBRS enabled and active:  NO
    * Kernel is compiled with IBPB support:  NO
    * IBPB enabled and active:  NO
  * Mitigation 2
    * Kernel has branch predictor hardening (arm):  YES
    * Kernel compiled with retpoline option:  NO
  > STATUS:  NOT VULNERABLE  (Branch predictor hardening mitigates the vulnerability)

  CVE-2017-5754 aka 'Variant 3, Meltdown, rogue data cache load'
  * Mitigated according to the /sys interface:  YES  (Not affected)
  * Kernel supports Page Table Isolation (PTI):  YES
    * PTI enabled and active:  UNKNOWN  (dmesg truncated, please reboot and relaunch this script)
    * Reduced performance impact of PTI:  NO  (PCID/INVPCID not supported, performance impact of PTI will be significant)
  * Running as a Xen PV DomU:  NO
  > STATUS:  NOT VULNERABLE  (your CPU vendor reported your CPU model as not vulnerable)

  CVE-2018-3640 aka 'Variant 3a, rogue system register read'
  * CPU microcode mitigates the vulnerability:  NO
  > STATUS:  NOT VULNERABLE  (your CPU vendor reported your CPU model as not vulnerable)

  CVE-2018-3639 aka 'Variant 4, speculative store bypass'
  * Mitigated according to the /sys interface:  NO  (Vulnerable)
  * Kernel supports disabling speculative store bypass (SSB):  YES  (found in /proc/self/status)
  * SSB mitigation is enabled and active: > STATUS:  VULNERABLE  (Your CPU doesn't support SSBD)

  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  (Not affected)
  * Kernel supports PTE inversion:  NO
  * PTE inversion enabled and active:  NO
  > STATUS:  NOT VULNERABLE  (your CPU vendor reported your CPU model as not vulnerable)

  CVE-2018-3646 aka 'Foreshadow-NG (VMM), L1 terminal fault'
  * Information from the /sys interface: Not affected
  * 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:  NO
    * L1D flush enabled:  NO
    * Hardware-backed L1D flush supported:  NO  (flush will be done in software, this is slower)
    * Hyper-Threading (SMT) is enabled:  UNKNOWN
  > STATUS:  NOT VULNERABLE  (your CPU vendor reported your CPU model as not vulnerable)

  CVE-2018-12126 aka 'Fallout, microarchitectural store buffer data sampling (MSBDS)'
  * Mitigated according to the /sys interface:  YES  (Not affected)
  * Kernel supports using MD_CLEAR mitigation:  NO
  * Kernel mitigation is enabled and active:  NO
  * SMT is either mitigated or disabled:  NO
  > STATUS:  NOT VULNERABLE  (your CPU vendor reported your CPU model as not vulnerable)

  CVE-2018-12130 aka 'ZombieLoad, microarchitectural fill buffer data sampling (MFBDS)'
  * Mitigated according to the /sys interface:  YES  (Not affected)
  * Kernel supports using MD_CLEAR mitigation:  NO
  * Kernel mitigation is enabled and active:  NO
  * SMT is either mitigated or disabled:  NO
  > STATUS:  NOT VULNERABLE  (your CPU vendor reported your CPU model as not vulnerable)

  CVE-2018-12127 aka 'RIDL, microarchitectural load port data sampling (MLPDS)'
  * Mitigated according to the /sys interface:  YES  (Not affected)
  * Kernel supports using MD_CLEAR mitigation:  NO
  * Kernel mitigation is enabled and active:  NO
  * SMT is either mitigated or disabled:  NO
  > STATUS:  NOT VULNERABLE  (your CPU vendor reported your CPU model as not vulnerable)

  CVE-2019-11091 aka 'RIDL, microarchitectural data sampling uncacheable memory (MDSUM)'
  * Mitigated according to the /sys interface:  YES  (Not affected)
  * Kernel supports using MD_CLEAR mitigation:  NO
  * Kernel mitigation is enabled and active:  NO
  * SMT is either mitigated or disabled:  NO
  > STATUS:  NOT VULNERABLE  (your CPU vendor reported your CPU model as not vulnerable)

  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:  YES  (Not affected)
  * 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  (your CPU vendor reported your CPU model as not vulnerable)

  CVE-2020-0543 aka 'Special Register Buffer Data Sampling (SRBDS)'
  * SRBDS mitigation control is supported by the kernel:  NO
  * SRBDS mitigation control is enabled and active:  NO  (SRBDS not found in sysfs hierarchy)
  > STATUS:  NOT VULNERABLE  (your CPU vendor reported your CPU model as not vulnerable)

  > SUMMARY: CVE-2017-5753:OK CVE-2017-5715:OK CVE-2017-5754:OK CVE-2018-3640:OK CVE-2018-3639:KO CVE-2018-3615:OK CVE-2018-3620:OK CVE-2018-3646:OK CVE-2018-12126:OK CVE-2018-12130:OK CVE-2018-12127:OK CVE-2019-11091:OK CVE-2019-11135:OK CVE-2018-12207:OK CVE-2020-0543:OK