CWE-98: Improper Control of Filename for Include/Require Statement in PHP Program ('PHP Remote File Inclusion')

Variant Draft Simple

CWE版本: 4.18

更新日期: 2025-09-09

弱点描述

The PHP application receives input from an upstream component, but it does not restrict or incorrectly restricts the input before its usage in "require," "include," or similar functions.

扩展描述

In certain versions and configurations of PHP, this can allow an attacker to specify a URL to a remote location from which the product will obtain the code to execute. In other cases in association with path traversal, the attacker can specify a local file that may contain executable statements that can be parsed by PHP.

常见后果

影响范围: Integrity Confidentiality Availability

技术影响: Execute Unauthorized Code or Commands

说明: The attacker may be able to specify arbitrary code to be executed from a remote location. Alternatively, it may be possible to use normal program behavior to insert php code into files on the local machine which can then be included and force the code to execute since php ignores everything in the file except for the content between php specifiers.

潜在缓解措施

阶段: Architecture and Design

策略: Libraries or Frameworks

描述: Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid [REF-1482].

阶段: Architecture and Design

策略: Enforcement by Conversion

阶段: Architecture and Design

描述: For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

阶段: Architecture and Design Operation

策略: Sandbox or Jail

有效性: Limited

阶段: Architecture and Design Operation

策略: Environment Hardening

描述: Run your code using the lowest privileges that are required to accomplish the necessary tasks [REF-76]. If possible, create isolated accounts with limited privileges that are only used for a single task. That way, a successful attack will not immediately give the attacker access to the rest of the software or its environment. For example, database applications rarely need to run as the database administrator, especially in day-to-day operations.

阶段: Implementation

策略: Input Validation

有效性: High

阶段: Architecture and Design Operation

策略: Attack Surface Reduction

阶段: Architecture and Design Implementation

策略: Attack Surface Reduction

阶段: Operation

策略: Firewall

描述: Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth [REF-1481].

有效性: Moderate

阶段: Operation Implementation

策略: Environment Hardening

描述: Develop and run your code in the most recent versions of PHP available, preferably PHP 6 or later. Many of the highly risky features in earlier PHP interpreters have been removed, restricted, or disabled by default.

阶段: Operation Implementation

策略: Environment Hardening

阶段: Operation

策略: Environment Hardening

描述: Set allow_url_fopen to false, which limits the ability to include files from remote locations.

有效性: High

检测方法

方法: Manual Analysis

Manual white-box analysis can be very effective for finding this issue, since there is typically a relatively small number of include or require statements in each program.

有效性: High

方法: Automated Static Analysis