cis-apache24-7-7

name	cis-apache24-7.7
description	Ensure SSL Compression is not Enabled (Manual)
category	cis-apache
version	2.3.0
author	cyberstrike-official
tags	["cis","apache","linux","ssl","tls","compression","crime"]
cis_id	7.7
cis_benchmark	CIS Apache HTTP Server 2.4 Benchmark v2.3.0
tech_stack	["linux","apache"]
cwe_ids	[]
chains_with	[]
prerequisites	[]
severity_boost	{}

Ensure SSL Compression is not Enabled (Manual)

Profile Applicability

• Level 1

Description

The SSLCompression directive controls whether SSL compression is used by Apache when serving content over HTTPS. It is recommended that the SSLCompression directive be set to off.

Rationale

If SSL compression is enabled, HTTPS communication between the client and the server may be at increased risk to the CRIME attack. The CRIME attack increases a malicious actor's ability to derive the value of a session cookie, which commonly contains an authenticator. If the authenticator in a session cookie is derived, it can be used to impersonate the account associated with the authenticator.

Audit

Perform the following steps to determine if the recommended state is implemented:

1. Search the Apache configuration files for the SSLCompression directive.
2. Verify that the directive either does not exist or exists and is set to off.

Remediation

Perform the following to implement the recommended state:

1. Search the Apache configuration files for the SSLCompression directive.
2. If the directive is present, set it to off.

SSLCompression off

Default Value

In Apache versions >= 2.4.3, the SSLCompression directive is available and SSL compression is implicitly disabled. In Apache 2.4 - 2.4.2, the SSLCompression directive is not available and SSL compression is implicitly disabled.

References

1. https://httpd.apache.org/docs/2.4/mod/mod_ssl.html#sslcompression
2. https://en.wikipedia.org/wiki/CRIME_(security_exploit)

CIS Controls

v8:

• 3.10 Encrypt Sensitive Data in Transit
  • Encrypt sensitive data in transit. Example implementations can include: Transport Layer Security (TLS) and Open Secure Shell (OpenSSH).

v7:

• 14.4 Encrypt All Sensitive Information in Transit
  • Encrypt all sensitive information in transit.

Profile

• Level 1