Title

A web site must not contain a robots.txt file. (Cat II impact)

Discussion

Search engines are constantly at work on the Internet. Search engines are augmented by agents, often referred to as spiders or bots, which endeavor to capture and catalog web-site content. In turn, these search engines make the content they obtain and catalog available to any public web user. To request that a well behaved search engine not crawl and catalog a site, the web site may contain a file called robots.txt. This file contains directories and files that the web server SA desires not be crawled or cataloged, but this file can also be used, by an attacker or poorly coded search engine, as a directory and file index to a site. This information may be used to reduce an attacker’s time searching and traversing the web site to find files that might be relevant. If information on the web site needs to be protected from search engines and public view, other methods must be used.

Check Content

Locate the Apache httpd.conf file. If unable to locate the file, perform a search of the system to find the location of the file. Open the httpd.conf file with an editor and search for the following uncommented directives: DocumentRoot & Alias Navigate to the location(s) specified in the Include statement(s), and review each file for the following uncommented directives: DocumentRoot & Alias At the top level of the directories identified after the enabled DocumentRoot & Alias directives, verify that a “robots.txt” file does not exist. If the file does exist, this is a finding.

Fix Text

Remove the robots.txt file from the web site. If there is information on the web site that needs protection from search engines and public view, then other methods must be used to safeguard the data.

Additional Identifiers

Rule ID: SV-28798r2_rule

Vulnerability ID: V-2260

Group Title: WG310

Expert Comments

CCIs tied to check.

Controls tied to check. These are derived from the CCIs shown above.