Amazon Linux AMI : kernel (ALAS-2023-1838)

high Nessus Plugin ID 182700

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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 4.14.326-171.539. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS-2023-1838 advisory.

- A flaw was found in the Linux kernel's IP framework for transforming packets (XFRM subsystem). This issue may allow a malicious user with CAP_NET_ADMIN privileges to directly dereference a NULL pointer in xfrm_update_ae_params(), leading to a possible kernel crash and denial of service. (CVE-2023-3772)

- A flaw was found in the Netfilter subsystem in the Linux kernel. The xt_u32 module did not validate the fields in the xt_u32 structure. This flaw allows a local privileged attacker to trigger an out-of-bounds read by setting the size fields with a value beyond the array boundaries, leading to a crash or information disclosure. (CVE-2023-39192)

- A flaw was found in the Netfilter subsystem in the Linux kernel. The sctp_mt_check did not validate the flag_count field. This flaw allows a local privileged (CAP_NET_ADMIN) attacker to trigger an out-of-bounds read, leading to a crash or information disclosure. (CVE-2023-39193)

- A flaw was found in the XFRM subsystem in the Linux kernel. The specific flaw exists within the processing of state filters, which can result in a read past the end of an allocated buffer. This flaw allows a local privileged (CAP_NET_ADMIN) attacker to trigger an out-of-bounds read, potentially leading to an information disclosure. (CVE-2023-39194)

- A use-after-free vulnerability in the Linux kernel's net/sched: cls_fw component can be exploited to achieve local privilege escalation. When fw_change() is called on an existing filter, the whole tcf_result struct is always copied into the new instance of the filter. This causes a problem when updating a filter bound to a class, as tcf_unbind_filter() is always called on the old instance in the success path, decreasing filter_cnt of the still referenced class and allowing it to be deleted, leading to a use-after- free. We recommend upgrading past commit 76e42ae831991c828cffa8c37736ebfb831ad5ec. (CVE-2023-4207)

- A use-after-free vulnerability in the Linux kernel's netfilter: nf_tables component can be exploited to achieve local privilege escalation. Due to a race condition between nf_tables netlink control plane transaction and nft_set element garbage collection, it is possible to underflow the reference counter causing a use-after-free vulnerability. We recommend upgrading past commit 3e91b0ebd994635df2346353322ac51ce84ce6d8. (CVE-2023-4244)

- An array indexing vulnerability was found in the netfilter subsystem of the Linux kernel. A missing macro could lead to a miscalculation of the `h->nets` array offset, providing attackers with the primitive to arbitrarily increment/decrement a memory buffer out-of-bound. This issue may allow a local user to crash the system or potentially escalate their privileges on the system. (CVE-2023-42753)

- A flaw was found in the IPv4 Resource Reservation Protocol (RSVP) classifier in the Linux kernel. The xprt pointer may go beyond the linear part of the skb, leading to an out-of-bounds read in the `rsvp_classify` function. This issue may allow a local user to crash the system and cause a denial of service.
(CVE-2023-42755)

- An issue was discovered in drivers/net/ethernet/intel/igb/igb_main.c in the IGB driver in the Linux kernel before 6.5.3. A buffer size may not be adequate for frames larger than the MTU. (CVE-2023-45871)

- A use-after-free vulnerability in the Linux kernel's af_unix component can be exploited to achieve local privilege escalation. The unix_stream_sendpage() function tries to add data to the last skb in the peer's recv queue without locking the queue. Thus there is a race where unix_stream_sendpage() could access an skb locklessly that is being released by garbage collection, resulting in use-after-free. We recommend upgrading past commit 790c2f9d15b594350ae9bca7b236f2b1859de02c. (CVE-2023-4622)

- A use-after-free vulnerability in the Linux kernel's net/sched: sch_hfsc (HFSC qdisc traffic control) component can be exploited to achieve local privilege escalation. If a class with a link-sharing curve (i.e. with the HFSC_FSC flag set) has a parent without a link-sharing curve, then init_vf() will call vttree_insert() on the parent, but vttree_remove() will be skipped in update_vf(). This leaves a dangling pointer that can cause a use-after-free. We recommend upgrading past commit b3d26c5702c7d6c45456326e56d2ccf3f103e60f. (CVE-2023-4623)

- A use-after-free vulnerability in the Linux kernel's net/sched: sch_qfq component can be exploited to achieve local privilege escalation. When the plug qdisc is used as a class of the qfq qdisc, sending network packets triggers use-after-free in qfq_dequeue() due to the incorrect .peek handler of sch_plug and lack of error checking in agg_dequeue(). We recommend upgrading past commit 8fc134fee27f2263988ae38920bc03da416b03d8. (CVE-2023-4921)

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

Severity: High

ID: 182700

File Name: ala_ALAS-2023-1838.nasl

Version: 1.6

Type: local

Agent: unix

Family: Amazon Linux Local Security Checks

Published: 10/6/2023

Updated: 3/19/2024

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: Medium

Base Score: 6.8

Temporal Score: 5.3

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

CVSS Score Source: CVE-2023-4921

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

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: 9/27/2023

Vulnerability Publication Date: 7/25/2023

Reference Information

CVE: CVE-2023-3772, CVE-2023-39192, CVE-2023-39193, CVE-2023-39194, CVE-2023-4207, CVE-2023-4244, CVE-2023-42753, CVE-2023-42755, CVE-2023-45871, CVE-2023-4622, CVE-2023-4623, CVE-2023-4921

Detections

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