COMMON ATTACK PATTERN ENUMERATION AND CLASSIFICATIONLive MITRE record

CAPEC-48

Passing Local Filenames to Functions That Expect a URL

This attack relies on client side code to access local files and resources instead of URLs. When the client browser is expecting a URL string, but instead receives a request for a local file, that execution is likely to occur in the browser process space with the browser's authority to local files. The attacker can send the results of this request to the local files out to a site that they control. This attack may be used to steal sensitive authentication data (either local or remote), or to gain system profile information to launch further attacks.

Abstraction

Standard

Typical severity

High

Likelihood of attack

High

Understand the attack

What is this attack pattern?

This attack relies on client side code to access local files and resources instead of URLs. When the client browser is expecting a URL string, but instead receives a request for a local file, that execution is likely to occur in the browser process space with the browser's authority to local files. The attacker can send the results of this request to the local files out to a site that they control. This attack may be used to steal sensitive authentication data (either local or remote), or to gain system profile information to launch further attacks.

Execution flow

How does the attack proceed, step by step?

1

Explore

Identify web application URL inputs

Review application inputs to find those that are designed to be URLs.

Techniques used

  • Manually navigate web site pages to identify URLs.
  • Use automated tools to identify URLs.
2

Experiment

Identify URL inputs allowing local access.

Execute test local commands via each URL input to determine which are successful.

Techniques used

  • Manually execute a local command (such as 'pwd') via the URL inputs.
  • Using an automated tool, test each URL input for weakness.
3

Exploit

Execute malicious commands

Using the identified URL inputs that allow local command execution, execute malicious commands.

Techniques used

  • Execute local commands via the URL input.

Requirements

What does the attack require?

Prerequisites

  • The victim's software must not differentiate between the location and type of reference passed the client software, e.g. browser

Skills required

  • Medium: Attacker identifies known local files to exploit

Resources required

Not stated in the MITRE record.

Impact

What does a successful attack lead to?

Read Data

Affected scopes: Confidentiality

Modify Data

Affected scopes: Integrity

Defence

How is it prevented and mitigated?

1
Implementation: Ensure all content that is delivered to client is sanitized against an acceptable content specification.
2
Implementation: Ensure all configuration files and resource are either removed or protected when promoting code into production.
3
Design: Use browser technologies that do not allow client side scripting.
4
Implementation: Perform input validation for all remote content.
5
Implementation: Perform output validation for all remote content.
6
Implementation: Disable scripting languages such as JavaScript in browser

Real world

MITRE example instances

Example instance 1Detail
J2EE applications frequently use .properties files to store configuration information including JDBC connections, LDAP connection strings, proxy information, system passwords and other system metadata that is valuable to attackers looking to probe the system or bypass policy enforcement points. When these files are stored in publicly accessible directories and are allowed to be read by the public user, then an attacker can list the directory identify a .properties file and simply load its contents in the browser listing its contents. A standard Hibernate properties file contains hibernate.connection.driver_class = org.postgresql.Driver hibernate.connection.url = jdbc:postgresql://localhost/mydatabase hibernate.connection.username = username hibernate.connection.password = password hibernate.c3p0.min_size=5 hibernate.c3p0.max_size=20 Even if the attacker cannot write this file, there is plenty of information to leverage to gain further access.
CAPEC-48: Passing Local Filenames to Functions That Expect a URL — DayBreach Saldırı Sözlüğü · DayBreach