Amazon Linux 2 : amazon-ssm-agent (ALAS-2023-2303)

critical Nessus Plugin ID 183477

Synopsis

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

Description

The version of amazon-ssm-agent installed on the remote host is prior to 3.2.1705.0-1. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2-2023-2303 advisory.

2023-10-30: CVE-2023-29409 was added to this advisory.

2023-10-30: CVE-2023-3978 was added to this advisory.

2023-10-30: CVE-2023-29406 was added to this advisory.

2023-10-30: CVE-2023-24540 was added to this advisory.

The x/crypto/ssh package before 0.0.0-20211202192323-5770296d904e of golang.org/x/crypto allows an attacker to panic an SSH server. (CVE-2021-43565)

http2/hpack: avoid quadratic complexity in hpack decoding (CVE-2022-41723)

Templates did not properly consider backticks (`) as Javascript string delimiters, and as such didnot escape them as expected. Backticks are used, since ES6, for JS template literals. If a templatecontained a Go template action within a Javascript template literal, the contents of the action couldbe used to terminate the literal, injecting arbitrary Javascript code into the Go template. (CVE-2023-24538)

html/template: improper handling of JavaScript whitespace.

Not all valid JavaScript whitespace characters were considered to be whitespace. Templates containing whitespace characters outside of the character set \t\n\f\r\u0020\u2028\u2029 in JavaScript contexts that also contain actions may not be properly sanitized during execution. (CVE-2023-24540)

The HTTP/1 client does not fully validate the contents of the Host header. A maliciously crafted Host header can inject additional headers or entire requests. With fix, the HTTP/1 client now refuses to send requests containing an invalid Request.Host or Request.URL.Host value. (CVE-2023-29406)

Extremely large RSA keys in certificate chains can cause a client/server to expend significant CPU time verifying signatures. With fix, the size of RSA keys transmitted during handshakes is restricted to <= 8192 bits. Based on a survey of publicly trusted RSA keys, there are currently only three certificates in circulation with keys larger than this, and all three appear to be test certificates that are not actively deployed. It is possible there are larger keys in use in private PKIs, but we target the web PKI, so causing breakage here in the interests of increasing the default safety of users of crypto/tls seems reasonable. (CVE-2023-29409)

Text nodes not in the HTML namespace are incorrectly literally rendered, causing text which should be escaped to not be. This could lead to an XSS attack. (CVE-2023-3978)

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 amazon-ssm-agent' to update your system.

See Also

https://alas.aws.amazon.com/AL2/ALAS-2023-2303.html

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

https://alas.aws.amazon.com/cve/html/CVE-2021-43565.html

https://alas.aws.amazon.com/cve/html/CVE-2022-41723.html

https://alas.aws.amazon.com/cve/html/CVE-2023-24538.html

https://alas.aws.amazon.com/cve/html/CVE-2023-24540.html

https://alas.aws.amazon.com/cve/html/CVE-2023-29406.html

https://alas.aws.amazon.com/cve/html/CVE-2023-29409.html

https://alas.aws.amazon.com/cve/html/CVE-2023-3978.html

Plugin Details

Severity: Critical

ID: 183477

File Name: al2_ALAS-2023-2303.nasl

Version: 1.2

Type: local

Agent: unix

Published: 10/20/2023

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: 6.7

CVSS v2

Risk Factor: Critical

Base Score: 10

Temporal Score: 7.4

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

CVSS Score Source: CVE-2023-24540

CVSS v3

Risk Factor: Critical

Base Score: 9.8

Temporal Score: 8.5

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

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

CVSS v4

Risk Factor: Critical

Base Score: 9.3

Threat Score: 8.1

Threat Vector: CVSS:4.0/E:U

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

CVSS Score Source: CVE-2023-3978

Vulnerability Information

CPE: p-cpe:/a:amazon:linux:amazon-ssm-agent-debuginfo, cpe:/o:amazon:linux:2, p-cpe:/a:amazon:linux:amazon-ssm-agent

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

Exploit Ease: No known exploits are available

Patch Publication Date: 10/12/2023

Vulnerability Publication Date: 4/7/2022

Reference Information

CVE: CVE-2021-43565, CVE-2022-41723, CVE-2023-24538, CVE-2023-24540, CVE-2023-29406, CVE-2023-29409, CVE-2023-3978

IAVB: 2023-B-0012-S, 2023-B-0022-S