Oracle Linux 7 / 8 : Unbreakable Enterprise kernel (ELSA-2020-5848)

medium Nessus Plugin ID 140588
New! Plugin Severity Now Using CVSS v3

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Synopsis

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

Description

The remote Oracle Linux 7 / 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2020-5848 advisory.

- A flaw was found in the Linux kernels implementation of the invert video code on VGA consoles when a local attacker attempts to resize the console, calling an ioctl VT_RESIZE, which causes an out-of-bounds write to occur. This flaw allows a local user with access to the VGA console to crash the system, potentially escalating their privileges on the system. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability. (CVE-2020-14331)

- In the Linux kernel before 5.7.8, fs/nfsd/vfs.c (in the NFS server) can set incorrect permissions on new filesystem objects when the filesystem lacks ACL support, aka CID-22cf8419f131. This occurs because the current umask is not considered. (CVE-2020-24394)

- A flaw was found in the Linux Kernel before 5.8-rc6 in the ZRAM kernel module, where a user with a local account and the ability to read the /sys/class/zram-control/hot_add file can create ZRAM device nodes in the /dev/ directory. This read allocates kernel memory and is not accounted for a user that triggers the creation of that ZRAM device. With this vulnerability, continually reading the device may consume a large amount of system memory and cause the Out-of-Memory (OOM) killer to activate and terminate random userspace processes, possibly making the system inoperable. (CVE-2020-10781)

- The Linux kernel through 5.7.11 allows remote attackers to make observations that help to obtain sensitive information about the internal state of the network RNG, aka CID-f227e3ec3b5c. This is related to drivers/char/random.c and kernel/time/timer.c. (CVE-2020-16166)

- A flaw was found in the Linux kernels SELinux LSM hook implementation before version 5.7, where it incorrectly assumed that an skb would only contain a single netlink message. The hook would incorrectly only validate the first netlink message in the skb and allow or deny the rest of the messages within the skb with the granted permission without further processing. (CVE-2020-10751)

- An issue was discovered in the Linux kernel through 5.6.11. btree_gc_coalesce in drivers/md/bcache/btree.c has a deadlock if a coalescing operation fails. (CVE-2020-12771)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Update the affected packages.

See Also

https://linux.oracle.com/errata/ELSA-2020-5848.html

Plugin Details

Severity: Medium

ID: 140588

File Name: oraclelinux_ELSA-2020-5848.nasl

Version: 1.3

Type: local

Agent: unix

Published: 9/15/2020

Updated: 9/8/2021

Dependencies: linux_alt_patch_detect.nasl, ssh_get_info.nasl

Risk Information

CVSS Score Source: CVE-2020-14331

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: High

Base Score: 7.2

Temporal Score: 5.3

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

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3

Risk Factor: Medium

Base Score: 6.6

Temporal Score: 5.8

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

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/o:oracle:linux:7, cpe:/o:oracle:linux:8, p-cpe:/a:oracle:linux:kernel-uek, p-cpe:/a:oracle:linux:kernel-uek-debug, p-cpe:/a:oracle:linux:kernel-uek-debug-devel, p-cpe:/a:oracle:linux:kernel-uek-devel, p-cpe:/a:oracle:linux:kernel-uek-doc, p-cpe:/a:oracle:linux:kernel-uek-tools, p-cpe:/a:oracle:linux:kernel-uek-tools-libs, p-cpe:/a:oracle:linux:perf, p-cpe:/a:oracle:linux:python-perf

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

Exploit Ease: No known exploits are available

Patch Publication Date: 9/14/2020

Vulnerability Publication Date: 5/9/2020

Reference Information

CVE: CVE-2020-10751, CVE-2020-10781, CVE-2020-12771, CVE-2020-14331, CVE-2020-16166, CVE-2020-24394