Scientific Linux Security Update : kernel on SL6.x i386/x86_64 (Spectre)

Medium Nessus Plugin ID 110024

Synopsis

The remote Scientific Linux host is missing one or more security updates.

Description

Security Fix(es) :

- An industry-wide issue was found in the way many modern microprocessor designs have implemented speculative execution of Load & Store instructions (a commonly used performance optimization). It relies on the presence of a precisely-defined instruction sequence in the privileged code as well as the fact that memory read from address to which a recent memory write has occurred may see an older value and subsequently cause an update into the microprocessor's data cache even for speculatively executed instructions that never actually commit (retire). As a result, an unprivileged attacker could use this flaw to read privileged memory by conducting targeted cache side-channel attacks.
(CVE-2018-3639)

Note: This issue is present in hardware and cannot be fully fixed via software update. The updated kernel packages provide software side of the mitigation for this hardware issue. To be fully functional, up-to-date CPU microcode applied on the system is required.

In this update mitigations for x86 (both 32 and 64 bit) architecture are provided.

Bug Fix(es) :

- Previously, an erroneous code in the x86 kexec system call path caused a memory corruption. As a consequence, the system became unresponsive with the following kernel stack trace :

'WARNING: CPU: 13 PID: 36409 at lib/list_debug.c:59
__list_del_entry+0xa1/0xd0 list_del corruption. prev->next should be ffffdd03fddeeca0, but was (null)'

This update ensures that the code does not corrupt memory. As a result, the operating system no longer hangs.

Solution

Update the affected packages.

See Also

http://www.nessus.org/u?220e9f30

Plugin Details

Severity: Medium

ID: 110024

File Name: sl_20180522_kernel_on_SL6_x.nasl

Version: 1.8

Type: local

Agent: unix

Published: 2018/05/23

Updated: 2019/04/05

Dependencies: 12634

Risk Information

Risk Factor: Medium

CVSS v2.0

Base Score: 4.9

Temporal Score: 3.8

Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:N/A:N

Temporal Vector: CVSS2#E:POC/RL:OF/RC:C

CVSS v3.0

Base Score: 5.5

Temporal Score: 5

Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C

Vulnerability Information

CPE: x-cpe:/o:fermilab:scientific_linux

Required KB Items: Host/local_checks_enabled, Host/cpu, Host/RedHat/release, Host/RedHat/rpm-list

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 2018/05/22

Reference Information

CVE: CVE-2018-3639