Privilege Chaining
Draft Base
Structure: Simple
Description
Two distinct privileges, roles, capabilities, or rights can be combined in a way that allows an entity to perform unsafe actions that would not be allowed without that combination.
Common Consequences 1
Scope: Access Control
Impact: Gain Privileges or Assume Identity
A user can be given or gain access rights of another user. This can give the user unauthorized access to sensitive information including the access information of another user.
Potential Mitigations 3
Phase: Architecture and Design
Strategy: Separation of Privilege
Consider following the principle of separation of privilege. Require multiple conditions to be met before permitting access to a system resource.
Phase: Architecture and DesignOperation
Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.
Phase: Architecture and DesignOperation
Strategy: Environment Hardening
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.
Demonstrative Examples 1
ID : DX-128
This code allows someone with the role of "ADMIN" or "OPERATOR" to reset a user's password. The role of "OPERATOR" is intended to have less privileges than an "ADMIN", but still be able to help users with small issues such as forgotten passwords.Code Example:
Bad
Java
javaThis code does not check the role of the user whose password is being reset. It is possible for an Operator to gain Admin privileges by resetting the password of an Admin account and taking control of that account.
Observed Examples 4
CVE-2005-1736Chaining of user rights.
CVE-2002-1772Gain certain rights via privilege chaining in alternate channel.
CVE-2005-1973Application is allowed to assign extra permissions to itself.
CVE-2003-0640"operator" user can overwrite usernames and passwords to gain admin privileges.
References 1
Least Privilege
Sean Barnum and Michael Gegick
14-09-2005
ID: REF-76
Likelihood of Exploit
High
Applicable Platforms
Languages:
Not Language-Specific : Undetermined
Modes of Introduction
Architecture and Design
Implementation
Operation
Related Weaknesses
Taxonomy Mapping
- PLOVER
Notes
RelationshipThere is some conceptual overlap with Unsafe Privilege.