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 long delays. Where the key or parameters that are being checked have been obtained from an untrusted source this may lead to a Denial of Service. The function DH_check() performs various checks on DH parameters. After fixing CVE-2023-3446 it was discovered that a large q parameter value can also trigger an overly long computation during some of these checks. A correct q value, if present, cannot be larger than the modulus p parameter, thus it is unnecessary to perform these checks if q is larger than p. An application that calls DH_check() and supplies a key or parameters obtained from 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() and EVP_PKEY_param_check().
Also vulnerable are the OpenSSL dhparam and pkeyparam command line applications when 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)

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: 1.0

Type: local

Agent: unix

Published: 8/23/2023

Updated: 8/23/2023

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

Risk Information

VPR

Risk Factor: Low

Score: 2.9

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