Reg : Spectre & Meltdown

From: Mohammed Azfar
Date: Mon Jan 15 2018 - 16:14:59 EST


Hi Team

please share your suggestions about this.

I tired an online tool to check the vulnerability of spectre and meltdown, this is after upgrading 4.4.111-1 kernel version in centos 7. But its still showing in vulnerable state, im running this script in AWS instance. Please advice me.

Script : https://raw.githubusercontent.com/speed47/spectre-meltdown-checker/master/spectre-meltdown-checker.sh

Output : 

Spectre and Meltdown mitigation detection tool v0.24


Checking for vulnerabilities against live running kernel Linux 4.4.111-1.el7.elrepo.x86_64 #1 SMP Wed Jan 10 13:12:02 EST 2018 x86_64


CVE-2017-5753 [bounds check bypass] aka 'Spectre Variant 1'
* Checking count of LFENCE opcodes in kernel:  NO  (only 35 opcodes found, should be >= 70)
> STATUS:  VULNERABLE  (heuristic to be improved when official patches become available)


CVE-2017-5715 [branch target injection] aka 'Spectre Variant 2'
* Mitigation 1
*   Hardware (CPU microcode) support for mitigation:  YES
*   Kernel support for IBRS:  NO
*   IBRS enabled for Kernel space:  NO
*   IBRS enabled for User space:  NO
* Mitigation 2
*   Kernel compiled with retpoline option:  NO
*   Kernel compiled with a retpoline-aware compiler:  NO
> STATUS:  VULNERABLE  (IBRS hardware + kernel support OR kernel with retpoline are needed to mitigate the vulnerability)


CVE-2017-5754 [rogue data cache load] aka 'Meltdown' aka 'Variant 3'
* Kernel supports Page Table Isolation (PTI):  YES
* PTI enabled and active:  YES
> STATUS:  NOT VULNERABLE  (PTI mitigates the vulnerability)


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


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Thanks


Mohammed Azfar