COMMON WEAKNESS ENUMERATIONIncomplete

CWE-271

Privilege Dropping / Lowering Errors

The product does not drop privileges before passing control of a resource to an actor that does not have those privileges.

Abstraction

Class

Structure

Simple

Likelihood of Exploit

High

Understand the problem

What is the problem?

The product does not drop privileges before passing control of a resource to an actor that does not have those privileges.

Extended description

In some contexts, a system executing with elevated permissions will hand off a process/file/etc. to another process or user. If the privileges of an entity are not reduced, then elevated privileges are spread throughout a system and possibly to an attacker.

Root cause

How and when does the problem arise?

Lifecycle phase

Architecture and Design

Lifecycle phase

Implementation

REALIZATION: This weakness is caused during implementation of an architectural security tactic.

Lifecycle phase

Operation

Risk

What does successful exploitation lead to?

Gain Privileges or Assume Identity

Affected security scopes: Access Control

If privileges are not dropped, neither are access rights of the user. Often these rights can be prevented from being dropped.
Gain Privileges or Assume IdentityHide Activities

Affected security scopes: Access Control, Non-Repudiation

If privileges are not dropped, in some cases the system may record actions as the user which is being impersonated rather than the impersonator.

Defence

How is it prevented and fixed?

Architecture and Design

Separation of Privilege

Detail
Compartmentalize the system to have "safe" areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.

Architecture and Design · Operation

Defence to apply across several lifecycle phases

Detail
Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.

Architecture and Design

Separation of Privilege

Detail
Consider following the principle of separation of privilege. Require multiple conditions to be met before permitting access to a system resource.
CWE-271: Common Weakness Enumeration Entry CWE-271 · DayBreach Sözlük · DayBreach