Amazon Linux 2 : kernel (ALAS-2021-1719)

high Nessus Plugin ID 154914

Synopsis

The remote Amazon Linux 2 host is missing a security update.

Description

The version of kernel installed on the remote host is prior to 4.14.252-195.481. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2-2021-1719 advisory.

- A memory leak in the ccp_run_sha_cmd() function in drivers/crypto/ccp/ccp-ops.c in the Linux kernel through 5.3.9 allows attackers to cause a denial of service (memory consumption), aka CID-128c66429247.
(CVE-2019-18808)

- A flaw was found in the Linux kernel. A corrupted timer tree caused the task wakeup to be missing in the timerqueue_add function in lib/timerqueue.c. This flaw allows a local attacker with special user privileges to cause a denial of service, slowing and eventually stopping the system while running OSP.
(CVE-2021-20317)

- hso_free_net_device in drivers/net/usb/hso.c in the Linux kernel through 5.13.4 calls unregister_netdev without checking for the NETREG_REGISTERED state, leading to a use-after-free and a double free.
(CVE-2021-37159)

- arch/mips/net/bpf_jit.c in the Linux kernel before 5.4.10 can generate undesirable machine code when transforming unprivileged cBPF programs, allowing execution of arbitrary code within the kernel context.
This occurs because conditional branches can exceed the 128 KB limit of the MIPS architecture.
(CVE-2021-38300)

- prealloc_elems_and_freelist in kernel/bpf/stackmap.c in the Linux kernel through 5.14.9 allows unprivileged users to trigger an eBPF multiplication integer overflow with a resultant out-of-bounds write. (CVE-2021-41864)

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

Solution

Run 'yum update kernel' to update your system.

See Also

https://alas.aws.amazon.com/AL2/ALAS-2021-1719.html

https://access.redhat.com/security/cve/CVE-2021-20317

https://access.redhat.com/security/cve/CVE-2021-20321

https://access.redhat.com/security/cve/CVE-2021-37159

https://access.redhat.com/security/cve/CVE-2021-3744

https://access.redhat.com/security/cve/CVE-2021-3764

https://access.redhat.com/security/cve/CVE-2021-38300

https://access.redhat.com/security/cve/CVE-2021-41864

Plugin Details

Severity: High

ID: 154914

File Name: al2_ALAS-2021-1719.nasl

Version: 1.2

Type: local

Agent: unix

Published: 11/5/2021

Updated: 11/5/2021

Supported Sensors: Frictionless Assessment Agent, Frictionless Assessment AWS, Nessus Agent

Risk Information

CVSS Score Source: CVE-2021-38300

VPR

Risk Factor: Medium

Score: 5.9

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: High

Base Score: 7.8

Temporal Score: 6.8

Vector: CVSS:3.0/AV:L/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: p-cpe:/a:amazon:linux:kernel, p-cpe:/a:amazon:linux:kernel-debuginfo, p-cpe:/a:amazon:linux:kernel-debuginfo-common-aarch64, p-cpe:/a:amazon:linux:kernel-debuginfo-common-x86_64, p-cpe:/a:amazon:linux:kernel-devel, p-cpe:/a:amazon:linux:kernel-headers, p-cpe:/a:amazon:linux:kernel-livepatch-4.14.252-195.481, p-cpe:/a:amazon:linux:kernel-tools, p-cpe:/a:amazon:linux:kernel-tools-debuginfo, p-cpe:/a:amazon:linux:kernel-tools-devel, p-cpe:/a:amazon:linux:perf, p-cpe:/a:amazon:linux:perf-debuginfo, p-cpe:/a:amazon:linux:python-perf, p-cpe:/a:amazon:linux:python-perf-debuginfo, cpe:/o:amazon:linux:2

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

Exploit Ease: No known exploits are available

Patch Publication Date: 10/28/2021

Vulnerability Publication Date: 11/7/2019

Reference Information

CVE: CVE-2019-18808, CVE-2021-3744, CVE-2021-3764, CVE-2021-20317, CVE-2021-20321, CVE-2021-37159, CVE-2021-38300, CVE-2021-41864

ALAS: 2021-1719