Amazon Linux 2 : microvm-kernel (ALASMICROVM-KERNEL-4.14-2023-001)

high Nessus Plugin ID 181942

Synopsis

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

Description

The version of microvm-kernel installed on the remote host is prior to 4.14.252-207.481. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2MICROVM-KERNEL-4.14-2023-001 advisory.

- 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)

- A race condition accessing file object in the Linux kernel OverlayFS subsystem was found in the way users do rename in specific way with OverlayFS. A local user could use this flaw to crash the system.
(CVE-2021-20321)

- 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)

- A memory leak flaw was found in the Linux kernel in the ccp_run_aes_gcm_cmd() function in drivers/crypto/ccp/ccp-ops.c, which allows attackers to cause a denial of service (memory consumption).
This vulnerability is similar with the older CVE-2019-18808. (CVE-2021-3744)

- A memory leak flaw was found in the Linux kernel's ccp_run_aes_gcm_cmd() function that allows an attacker to cause a denial of service. The vulnerability is similar to the older CVE-2019-18808. The highest threat from this vulnerability is to system availability. (CVE-2021-3764)

- 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 before 5.14.12 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 these issues but has instead relied only on the application's self-reported version number.

Solution

Run 'yum update microvm-kernel' to update your system.

See Also

https://alas.aws.amazon.com/AL2/ALASMICROVM-KERNEL-4.14-2023-001.html

https://alas.aws.amazon.com/cve/html/CVE-2021-20317.html

https://alas.aws.amazon.com/cve/html/CVE-2021-20321.html

https://alas.aws.amazon.com/cve/html/CVE-2021-37159.html

https://alas.aws.amazon.com/cve/html/CVE-2021-3744.html

https://alas.aws.amazon.com/cve/html/CVE-2021-3764.html

https://alas.aws.amazon.com/cve/html/CVE-2021-38300.html

https://alas.aws.amazon.com/cve/html/CVE-2021-41864.html

https://alas.aws.amazon.com/faqs.html

Plugin Details

Severity: High

ID: 181942

File Name: al2_ALASMICROVM-KERNEL-4_14-2023-001.nasl

Version: 1.1

Type: local

Agent: unix

Published: 9/27/2023

Updated: 9/28/2023

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

Risk Information

VPR

Risk Factor: Medium

Score: 6.7

CVSS v2

Risk Factor: High

Base Score: 7.2

Temporal Score: 5.6

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

CVSS Score Source: CVE-2021-38300

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 7

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

CVSS Score Source: CVE-2021-41864

Vulnerability Information

CPE: p-cpe:/a:amazon:linux:microvm-kernel, p-cpe:/a:amazon:linux:microvm-kernel-debuginfo, p-cpe:/a:amazon:linux:microvm-kernel-debuginfo-common-aarch64, p-cpe:/a:amazon:linux:microvm-kernel-debuginfo-common-x86_64, p-cpe:/a:amazon:linux:microvm-kernel-devel, p-cpe:/a:amazon:linux:microvm-kernel-headers, cpe:/o:amazon:linux:2

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

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 9/14/2023

Vulnerability Publication Date: 7/21/2021

Reference Information

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