Amazon Linux AMI : kernel (ALAS-2023-1688)

high Nessus Plugin ID 171855

Synopsis

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

Description

The version of kernel installed on the remote host is prior to 4.14.262-135.486. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS-2023-1688 advisory.

2024-04-30: CVE-2023-0047 was removed from this advisory (rejected).

2024-02-01: CVE-2023-0047 was added to this advisory.

2023-10-12: CVE-2021-3923 was added to this advisory.

A flaw in the processing of received ICMP errors (ICMP fragment needed and ICMP redirect) in the Linux kernel functionality was found to allow the ability to quickly scan open UDP ports. This flaw allows an off-path remote user to effectively bypass the source port UDP randomization. The highest threat from this vulnerability is to confidentiality and possibly integrity, because software that relies on UDP source port randomization are indirectly affected as well. (CVE-2021-20322)

A denial of service flaw for virtual machine guests in the Linux kernel's Xen hypervisor subsystem was found in the way users call some interrupts with high frequency from one of the guests.A local user could use this flaw to starve the resources resulting in a denial of service. (CVE-2021-28711)

A denial of service flaw for virtual machine guests in the Linux kernel's Xen hypervisor subsystem was found in the way users call some interrupts with high frequency from one of the guests.A local user could use this flaw to starve the resources resulting in a denial of service. (CVE-2021-28712)

A denial of service flaw for virtual machine guests in the Linux kernel's Xen hypervisor subsystem was found in the way users call some interrupts with high frequency from one of the guests.A local user could use this flaw to starve the resources resulting in a denial of service. (CVE-2021-28713)

Incoming data packets for a guest in the Linux kernel's netback driver are buffered until the guest is ready to process them. There are some measures taken for avoiding to pile up too much data, but those can be bypassed by the guest: The timeout could even never trigger if the guest manages to have only one free slot in its RX queue ring page and the next package would require more than one free slot, which may be the case when using GSO, XDP, or software hashing. (CVE-2021-28714)

Incoming data packets for a guest in the Linux kernel's netback driver are buffered until the guest is ready to process them. There are some measures taken for avoiding to pile up too much data, but those can be bypassed by the guest: There is a timeout how long the client side of an interface can stop consuming new packets before it is assumed to have stalled, but this timeout is rather long (60 seconds by default).
Using a UDP connection on a fast interface can easily accumulate gigabytes of data in that time.
(CVE-2021-28715)

A flaw was found in the Linux SCTP stack. A blind attacker may be able to kill an existing SCTP association through invalid chunks if the attacker knows the IP-addresses and port numbers being used and the attacker can send packets with spoofed IP addresses. (CVE-2021-3772)

A flaw was found in the Linux kernel's implementation of RDMA over infiniband. An attacker with a privileged local account can leak kernel stack information when issuing commands to the /dev/infiniband/rdma_cm device node. While this access is unlikely to leak sensitive user information, it can be further used to defeat existing kernel protection mechanisms. (CVE-2021-3923)

A memory leak flaw in the Linux kernel's hugetlbfs memory usage was found in the way the user maps some regions of memory twice using shmget() which are aligned to PUD alignment with the fault of some of the memory pages. A local user could use this flaw to get unauthorized access to some data. (CVE-2021-4002)

A data leak flaw was found in the way XFS_IOC_ALLOCSP IOCTL in the XFS filesystem allowed for size increase of files with unaligned size. A local attacker could use this flaw to leak data on the XFS filesystem otherwise not accessible to them. (CVE-2021-4155)

Tenable has extracted the preceding description block directly from the tested product 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

Run 'yum update kernel' to update your system.

See Also

https://alas.aws.amazon.com/ALAS-2023-1688.html

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

https://alas.aws.amazon.com/cve/html/CVE-2021-3772.html

https://alas.aws.amazon.com/cve/html/CVE-2021-3923.html

https://alas.aws.amazon.com/cve/html/CVE-2021-4002.html

https://alas.aws.amazon.com/cve/html/CVE-2021-4155.html

https://alas.aws.amazon.com/cve/html/CVE-2021-20322.html

https://alas.aws.amazon.com/cve/html/CVE-2021-28711.html

https://alas.aws.amazon.com/cve/html/CVE-2021-28712.html

https://alas.aws.amazon.com/cve/html/CVE-2021-28713.html

https://alas.aws.amazon.com/cve/html/CVE-2021-28714.html

https://alas.aws.amazon.com/cve/html/CVE-2021-28715.html

Plugin Details

Severity: High

ID: 171855

File Name: ala_ALAS-2023-1688.nasl

Version: 1.7

Type: local

Agent: unix

Published: 2/23/2023

Updated: 12/11/2024

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

Risk Information

VPR

Risk Factor: Medium

Score: 6.0

CVSS v2

Risk Factor: Medium

Base Score: 5.8

Temporal Score: 4.5

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

CVSS Score Source: CVE-2021-3772

CVSS v3

Risk Factor: High

Base Score: 7.4

Temporal Score: 6.7

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

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

CVSS Score Source: CVE-2021-20322

Vulnerability Information

CPE: p-cpe:/a:amazon:linux:perf, p-cpe:/a:amazon:linux:perf-debuginfo, p-cpe:/a:amazon:linux:kernel-tools-debuginfo, p-cpe:/a:amazon:linux:kernel-tools-devel, p-cpe:/a:amazon:linux:kernel-tools, p-cpe:/a:amazon:linux:kernel-devel, p-cpe:/a:amazon:linux:kernel, p-cpe:/a:amazon:linux:kernel-debuginfo, p-cpe:/a:amazon:linux:kernel-headers, p-cpe:/a:amazon:linux:kernel-debuginfo-common-i686, p-cpe:/a:amazon:linux:kernel-debuginfo-common-x86_64, cpe:/o:amazon:linux

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: 2/17/2023

Vulnerability Publication Date: 1/11/2021

Reference Information

CVE: CVE-2021-20322, CVE-2021-28711, CVE-2021-28712, CVE-2021-28713, CVE-2021-28714, CVE-2021-28715, CVE-2021-3772, CVE-2021-3923, CVE-2021-4002, CVE-2021-4155