Synopsis
The remote Red Hat host is missing one or more security updates for kernel-rt.
Description
The remote Redhat Enterprise Linux 6 host has packages installed that are affected by multiple vulnerabilities as referenced in the RHSA-2018:0181 advisory.
The kernel-rt packages provide the Real Time Linux Kernel, which enables fine-tuning for systems with extremely high determinism requirements.
Security Fix(es):
* A flaw was found in the Linux kernel's key management system where it was possible for an attacker to escalate privileges or crash the machine. If a user key gets negatively instantiated, an error code is cached in the payload area. A negatively instantiated key may be then be positively instantiated by updating it with valid data. However, the ->update key type method must be aware that the error code may be there. (CVE-2015-8539, Important)
* It was found that fanout_add() in 'net/packet/af_packet.c' in the Linux kernel, before version 4.13.6, allows local users to gain privileges via crafted system calls that trigger mishandling of packet_fanout data structures, because of a race condition (involving fanout_add and packet_do_bind) that leads to a use-after-free bug. (CVE-2017-15649, Important)
* A vulnerability was found in the Linux kernel where the keyctl_set_reqkey_keyring() function leaks the thread keyring. This allows an unprivileged local user to exhaust kernel memory and thus cause a DoS.
(CVE-2017-7472, Moderate)
Red Hat would like to thank Dmitry Vyukov of Google engineering for reporting CVE-2015-8539.
Bug Fix(es):
* The mlx5 driver has a number of configuration options, including the selective support for network protocols, such as InfiniBand and Ethernet. Due to a regression in the configuration of the MRG-RT kernel, the Ethernet mode of the driver was turned off. The regression has been resolved by enabling the mlx5 Ethernet mode, making the Ethernet protocol to work again. (BZ#1422778)
* The migrate_disable/enable() kernel operations are used to pin a thread to a CPU temporarily. This method is a kernel-rt specific. To keep RHEL-RT's kernel up-to-date with the latest real-time kernel, the migrate_disable/enable routine was updated to the version present on kernel v4.9-rt. However, this version showed to be problematic. The changes in the migrate_disable/enabled have been thus reverted to a stable version, avoiding the kernel BUG. (BZ#1507831)
* The kernel-rt packages have been upgraded to version 3.10.0-693.15.1.rt56.601, which provides a number of security and bug fixes over the previous version. (BZ#1519504)
Tenable has extracted the preceding description block directly from the Red Hat Enterprise Linux security advisory.
Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.
Solution
Update the RHEL kernel-rt package based on the guidance in RHSA-2018:0181.
Plugin Details
File Name: redhat-RHSA-2018-0181.nasl
Agent: unix
Supported Sensors: Agentless Assessment, Continuous Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Frictionless Assessment Azure, Nessus Agent, Nessus
Risk Information
Vendor
Vendor Severity: Important
Vector: CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C
Vector: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C
Vulnerability Information
CPE: p-cpe:/a:redhat:enterprise_linux:kernel-rt, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug-devel, p-cpe:/a:redhat:enterprise_linux:kernel-rt-devel, cpe:/o:redhat:enterprise_linux:6, p-cpe:/a:redhat:enterprise_linux:kernel-rt-trace-devel, p-cpe:/a:redhat:enterprise_linux:kernel-rt-vanilla-devel, p-cpe:/a:redhat:enterprise_linux:kernel-rt-firmware, p-cpe:/a:redhat:enterprise_linux:kernel-rt-trace, p-cpe:/a:redhat:enterprise_linux:kernel-rt-debug, p-cpe:/a:redhat:enterprise_linux:kernel-rt-doc, p-cpe:/a:redhat:enterprise_linux:kernel-rt-vanilla
Required KB Items: Host/local_checks_enabled, Host/RedHat/release, Host/RedHat/rpm-list, Host/cpu
Exploit Ease: Exploits are available
Patch Publication Date: 1/25/2018
Vulnerability Publication Date: 2/8/2016