CWE-250
Execution with Unnecessary Privileges
AI Translation Available
The product performs an operation at a privilege level that is higher than the minimum level required, which creates new weaknesses or amplifies the consequences of other weaknesses.
Status
draft
Abstraction
base
Likelihood
medium
Affected Platforms
Mobile
Technical Details
AI Translation
Common Consequences
confidentiality
integrity
availability
access control
Impacts
gain privileges or assume identity
execute unauthorized code or commands
read application data
dos: crash, exit, or restart
Detection Methods
manual analysis
black box
automated static analysis - binary or bytecode
manual static analysis - binary or bytecode
dynamic analysis with automated results interpretation
dynamic analysis with manual results interpretation
manual static analysis - source code
automated static analysis - source code
automated static analysis
architecture or design review
Potential Mitigations
Phases:
architecture and design
operation
implementation
system configuration
Descriptions:
•
When dropping privileges, ensure that they have been dropped successfully to avoid CWE-273. As protection mechanisms in the environment get stronger, privilege-dropping calls may fail even if it seems like they would always succeed.
•
Ensure that the software runs properly under the United States Government Configuration Baseline (USGCB) [REF-199] or an equivalent hardening configuration guide, which many organizations use to limit the attack surface and potential risk of deployed software.
•
Identify the functionality that requires additional privileges, such as access to privileged operating system resources. Wrap and centralize this functionality if possible, and isolate the privileged code as much as possible from other code [REF-76]. Raise privileges as late as possible, and drop them as soon as possible to avoid CWE-271. Avoid weaknesses such as CWE-288 and CWE-420 by protecting all possible communication channels that could interact with the privileged code, such as a secondary socket that is only intended to be accessed by administrators.
•
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.
•
Perform extensive input validation for any privileged code that must be exposed to the user and reject anything that does not fit your strict requirements.
•
If circumstances force you to run with extra privileges, then determine the minimum access level necessary. First identify the different permissions that the software and its users will need to perform their actions, such as file read and write permissions, network socket permissions, and so forth. Then explicitly allow those actions while denying all else [REF-76]. Perform extensive input validation and canonicalization to minimize the chances of introducing a separate vulnerability. This mitigation is much more prone to error than dropping the privileges in the first place.