Amazon Linux 2 : edk2 (ALAS-2023-2205)

medium Nessus Plugin ID 180089

Synopsis

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

Description

It is, therefore, affected by a vulnerability as referenced in the ALAS2-2023-2205 advisory.

Issue summary: Checking excessively long DH keys or parameters may be very slow.

Impact summary: Applications that use the functions DH_check(), DH_check_ex()or EVP_PKEY_param_check() to check a DH key or DH parameters may experience longdelays. Where the key or parameters that are being checked have been obtainedfrom an untrusted source this may lead to a Denial of Service.

The function DH_check() performs various checks on DH parameters. After fixingCVE-2023-3446 it was discovered that a large q parameter value can also triggeran overly long computation during some of these checks. A correct q value,if present, cannot be larger than the modulus p parameter, thus it isunnecessary to perform these checks if q is larger than p.

An application that calls DH_check() and supplies a key or parameters obtainedfrom an untrusted source could be vulnerable to a Denial of Service attack.

The function DH_check() is itself called by a number of other OpenSSL functions.An application calling any of those other functions may similarly be affected.The other functions affected by this are DH_check_ex() andEVP_PKEY_param_check().

Also vulnerable are the OpenSSL dhparam and pkeyparam command line applicationswhen using the -check option.

The OpenSSL SSL/TLS implementation is not affected by this issue.

The OpenSSL 3.0 and 3.1 FIPS providers are not affected by this issue. (CVE-2023-3817)

Tenable has extracted the preceding description block directly from the tested product security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Run 'yum update edk2' to update your system.

See Also

https://alas.aws.amazon.com/AL2/ALAS-2023-2205.html

https://alas.aws.amazon.com/cve/html/CVE-2023-3817.html

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

Plugin Details

Severity: Medium

ID: 180089

File Name: al2_ALAS-2023-2205.nasl

Version: 1.1

Type: local

Agent: unix

Published: 8/23/2023

Updated: 12/11/2024

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

Risk Information

VPR

Risk Factor: Low

Score: 2.2

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

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

CVSS Score Source: CVE-2023-3817

CVSS v3

Risk Factor: Medium

Base Score: 5.3

Temporal Score: 4.6

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

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

Vulnerability Information

CPE: p-cpe:/a:amazon:linux:edk2-tools-doc, p-cpe:/a:amazon:linux:edk2-ovmf, p-cpe:/a:amazon:linux:edk2-tools, cpe:/o:amazon:linux:2, p-cpe:/a:amazon:linux:edk2-tools-python, p-cpe:/a:amazon:linux:edk2-debuginfo, p-cpe:/a:amazon:linux:edk2-aarch64

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

Exploit Ease: No known exploits are available

Patch Publication Date: 8/17/2023

Vulnerability Publication Date: 7/13/2023

Reference Information

CVE: CVE-2023-3817