Amazon Linux 2 : httpd (ALAS-2021-1674)

critical Nessus Plugin ID 151272

Language:

Synopsis

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

Description

The version of httpd installed on the remote host is prior to 2.4.48-2. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2-2021-1674 advisory.

- Apache HTTP Server versions 2.4.6 to 2.4.46 mod_proxy_wstunnel configured on an URL that is not necessarily Upgraded by the origin server was tunneling the whole connection regardless, thus allowing for subsequent requests on the same connection to pass through with no HTTP validation, authentication or authorization possibly configured. (CVE-2019-17567)

- Apache HTTP Server versions 2.4.0 to 2.4.46 Unprivileged local users can stop httpd on Windows (CVE-2020-13938)

- Apache HTTP Server versions 2.4.41 to 2.4.46 mod_proxy_http can be made to crash (NULL pointer dereference) with specially crafted requests using both Content-Length and Transfer-Encoding headers, leading to a Denial of Service (CVE-2020-13950)

- Apache HTTP Server versions 2.4.0 to 2.4.46 A specially crafted Digest nonce can cause a stack overflow in mod_auth_digest. There is no report of this overflow being exploitable, nor the Apache HTTP Server team could create one, though some particular compiler and/or compilation option might make it possible, with limited consequences anyway due to the size (a single byte) and the value (zero byte) of the overflow (CVE-2020-35452)

- Apache HTTP Server versions 2.4.0 to 2.4.46 A specially crafted Cookie header handled by mod_session can cause a NULL pointer dereference and crash, leading to a possible Denial Of Service (CVE-2021-26690)

- In Apache HTTP Server versions 2.4.0 to 2.4.46 a specially crafted SessionHeader sent by an origin server could cause a heap overflow (CVE-2021-26691)

- Apache HTTP Server versions 2.4.39 to 2.4.46 Unexpected matching behavior with 'MergeSlashes OFF' (CVE-2021-30641)

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 httpd' to update your system.

Plugin Details

Severity: Critical

ID: 151272

File Name: al2_ALAS-2021-1674.nasl

Version: 1.3

Type: local

Agent: unix

Family: Amazon Linux Local Security Checks

Published: 7/1/2021

Updated: 9/24/2021

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: High

Base Score: 7.5

Temporal Score: 5.5

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

CVSS Score Source: CVE-2021-26691

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

Vulnerability Information

CPE: p-cpe:/a:amazon:linux:httpd-tools, p-cpe:/a:amazon:linux:mod_ldap, p-cpe:/a:amazon:linux:mod_proxy_html, p-cpe:/a:amazon:linux:mod_session, p-cpe:/a:amazon:linux:mod_ssl, cpe:/o:amazon:linux:2, p-cpe:/a:amazon:linux:httpd-devel, p-cpe:/a:amazon:linux:httpd-debuginfo, p-cpe:/a:amazon:linux:mod_md, p-cpe:/a:amazon:linux:httpd, p-cpe:/a:amazon:linux:httpd-manual, p-cpe:/a:amazon:linux:httpd-filesystem

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

Exploit Ease: No known exploits are available

Patch Publication Date: 7/1/2021

Vulnerability Publication Date: 6/1/2021

Reference Information

CVE: CVE-2019-17567, CVE-2020-13938, CVE-2020-13950, CVE-2020-35452, CVE-2021-26690, CVE-2021-26691, CVE-2021-30641

ALAS: 2021-1674

IAVA: 2021-A-0259-S

Detections

Analytics