Amazon Linux 2 : kernel (ALASKERNEL-5.10-2022-012)

high Nessus Plugin ID 160433

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 5.10.106-102.504. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2KERNEL-5.10-2022-012 advisory.

- In the Linux kernel, the following vulnerability has been resolved: mm/damon/dbgfs: fix 'struct pid' leaks in 'dbgfs_target_ids_write()' DAMON debugfs interface increases the reference counts of 'struct pid's for targets from the 'target_ids' file write callback ('dbgfs_target_ids_write()'), but decreases the counts only in DAMON monitoring termination callback ('dbgfs_before_terminate()'). Therefore, when 'target_ids' file is repeatedly written without DAMON monitoring start/termination, the reference count is not decreased and therefore memory for the 'struct pid' cannot be freed. This commit fixes this issue by decreasing the reference counts when 'target_ids' is written. (CVE-2021-46937)

- A flaw was found in unrestricted eBPF usage by the BPF_BTF_LOAD, leading to a possible out-of-bounds memory write in the Linux kernel's BPF subsystem due to the way a user loads BTF. This flaw allows a local user to crash or escalate their privileges on the system. (CVE-2022-0500)

- A use-after-free flaw was found in the Linux kernel's FUSE filesystem in the way a user triggers write().
This flaw allows a local user to gain unauthorized access to data from the FUSE filesystem, resulting in privilege escalation. (CVE-2022-1011)

- A flaw was found in the Linux kernel in linux/net/netfilter/nf_tables_api.c of the netfilter subsystem.
This flaw allows a local user to cause an out-of-bounds write issue. (CVE-2022-1015)

- A flaw was found in the Linux kernel in net/netfilter/nf_tables_core.c:nft_do_chain, which can cause a use-after-free. This issue needs to handle 'return' with proper preconditions, as it can lead to a kernel information leak problem caused by a local, unprivileged attacker. (CVE-2022-1016)

- Linux PV device frontends vulnerable to attacks by backends T[his CNA information record relates to multiple CVEs; the text explains which aspects/vulnerabilities correspond to which CVE.] Several Linux PV device frontends are using the grant table interfaces for removing access rights of the backends in ways being subject to race conditions, resulting in potential data leaks, data corruption by malicious backends, and denial of service triggered by malicious backends: blkfront, netfront, scsifront and the gntalloc driver are testing whether a grant reference is still in use. If this is not the case, they assume that a following removal of the granted access will always succeed, which is not true in case the backend has mapped the granted page between those two operations. As a result the backend can keep access to the memory page of the guest no matter how the page will be used after the frontend I/O has finished.
The xenbus driver has a similar problem, as it doesn't check the success of removing the granted access of a shared ring buffer. blkfront: CVE-2022-23036 netfront: CVE-2022-23037 scsifront: CVE-2022-23038 gntalloc: CVE-2022-23039 xenbus: CVE-2022-23040 blkfront, netfront, scsifront, usbfront, dmabuf, xenbus, 9p, kbdfront, and pvcalls are using a functionality to delay freeing a grant reference until it is no longer in use, but the freeing of the related data page is not synchronized with dropping the granted access. As a result the backend can keep access to the memory page even after it has been freed and then re-used for a different purpose. CVE-2022-23041 netfront will fail a BUG_ON() assertion if it fails to revoke access in the rx path. This will result in a Denial of Service (DoS) situation of the guest which can be triggered by the backend. CVE-2022-23042 (CVE-2022-23036, CVE-2022-23037, CVE-2022-23038, CVE-2022-23039, CVE-2022-23040, CVE-2022-23042)

- Certain Arm Cortex and Neoverse processors through 2022-03-08 do not properly restrict cache speculation, aka Spectre-BHB. An attacker can leverage the shared branch history in the Branch History Buffer (BHB) to influence mispredicted branches. Then, cache allocation can allow the attacker to obtain sensitive information. (CVE-2022-23960)

- net/netfilter/nf_dup_netdev.c in the Linux kernel 5.4 through 5.6.10 allows local users to gain privileges because of a heap out-of-bounds write. This is related to nf_tables_offload. (CVE-2022-25636)

- A heap buffer overflow flaw was found in IPsec ESP transformation code in net/ipv4/esp4.c and net/ipv6/esp6.c. This flaw allows a local attacker with a normal user privilege to overwrite kernel heap objects and may cause a local privilege escalation threat. (CVE-2022-27666)

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/AL2/ALASKERNEL-5.10-2022-012.html

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

https://alas.aws.amazon.com/cve/html/CVE-2021-46937.html

https://alas.aws.amazon.com/cve/html/CVE-2022-0500.html

https://alas.aws.amazon.com/cve/html/CVE-2022-1011.html

https://alas.aws.amazon.com/cve/html/CVE-2022-1015.html

https://alas.aws.amazon.com/cve/html/CVE-2022-1016.html

https://alas.aws.amazon.com/cve/html/CVE-2022-23036.html

https://alas.aws.amazon.com/cve/html/CVE-2022-23037.html

https://alas.aws.amazon.com/cve/html/CVE-2022-23038.html

https://alas.aws.amazon.com/cve/html/CVE-2022-23039.html

https://alas.aws.amazon.com/cve/html/CVE-2022-23040.html

https://alas.aws.amazon.com/cve/html/CVE-2022-23042.html

https://alas.aws.amazon.com/cve/html/CVE-2022-23960.html

https://alas.aws.amazon.com/cve/html/CVE-2022-25636.html

https://alas.aws.amazon.com/cve/html/CVE-2022-27666.html

Plugin Details

Severity: High

ID: 160433

File Name: al2_ALASKERNEL-5_10-2022-012.nasl

Version: 1.11

Type: local

Agent: unix

Published: 5/2/2022

Updated: 4/25/2024

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

Risk Information

VPR

Risk Factor: Critical

Score: 9.0

CVSS v2

Risk Factor: High

Base Score: 7.2

Temporal Score: 6.3

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

CVSS Score Source: CVE-2022-0500

CVSS v3

Risk Factor: High

Base Score: 7.8

Temporal Score: 7.5

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:H/RL:O/RC:C

CVSS Score Source: CVE-2022-27666

Vulnerability Information

CPE: p-cpe:/a:amazon:linux:bpftool, p-cpe:/a:amazon:linux:bpftool-debuginfo, 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-5.10.106-102.504, 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 Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 4/5/2022

Vulnerability Publication Date: 2/24/2022

Exploitable With

CANVAS (CANVAS)

Core Impact

Reference Information

CVE: CVE-2021-46937, CVE-2022-0500, CVE-2022-1011, CVE-2022-1015, CVE-2022-1016, CVE-2022-23036, CVE-2022-23037, CVE-2022-23038, CVE-2022-23039, CVE-2022-23040, CVE-2022-23042, CVE-2022-23960, CVE-2022-25636, CVE-2022-27666