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 4.14.262-135.489. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS-2022-1563 advisory.
    2025-01-30: CVE-2021-47483 was added to this advisory.
    2025-01-30: CVE-2021-47506 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 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)
    In the Linux kernel, the following vulnerability has been resolved:
    regmap: Fix possible double-free in regcache_rbtree_exit() (CVE-2021-47483)
    In the Linux kernel, the following vulnerability has been resolved:
    nfsd: fix use-after-free due to delegation race (CVE-2021-47506)
    The cgroup release_agent is called with call_usermodehelper. The function call_usermodehelper starts the     release_agent with a full set of capabilities. Therefore require capabilities when setting the     release_agent. (CVE-2022-0492)
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.
Plugin Details
File Name: ala_ALAS-2022-1563.nasl
Agent: unix
Supported Sensors: Agentless Assessment, Continuous Assessment, Frictionless Assessment Agent, Frictionless Assessment AWS, Nessus Agent, Nessus
Risk Information
Vector: CVSS2#AV:L/AC:M/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:F/RL:O/RC:C
Vulnerability Information
CPE: cpe:/o:amazon:linux, p-cpe:/a:amazon:linux:kernel, p-cpe:/a:amazon:linux:kernel-tools-debuginfo, p-cpe:/a:amazon:linux:kernel-tools-devel, p-cpe:/a:amazon:linux:perf-debuginfo, p-cpe:/a:amazon:linux:kernel-debuginfo, 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-tools, p-cpe:/a:amazon:linux:perf, p-cpe:/a:amazon:linux:kernel-debuginfo-common-i686
Required KB Items: Host/local_checks_enabled, Host/AmazonLinux/release, Host/AmazonLinux/rpm-list
Exploit Ease: Exploits are available
Patch Publication Date: 2/4/2022
Vulnerability Publication Date: 1/11/2021
Exploitable With
Metasploit (Docker cgroups Container Escape)
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-2021-4002, CVE-2021-4155, CVE-2021-47483, CVE-2021-47506, CVE-2022-0492