Incorrect Use of Privileged APIs |
| Weakness ID: 648 (Weakness Base) | Status: Incomplete |
DescriptionDescription Summary
Extended Description
When an application contains certain functions that perform operations requiring an elevated level of privilege, the caller of a privileged API must be careful to:
- ensure that assumptions made by the APIs is valid, such as validity of arguments
- account for known weaknesses in the design/implementation of the API
- call the API from a safe context
If the caller of the API does not follow these requirements, then it may allow a malicious user or process to elevate their privilege, hijack the process, or steal sensitive data.
For instance, it is important to know if privileged APIs fail to properly shed their privileges before returning to the caller or if the privileged function might make certain assumptions about the data, context or state information passed to it by the caller. It is important to always know when and how privileged APIs can be called in order to ensure that their elevated level of privilege cannot be exploited.
Time of Introduction- Architecture and Design
- Implementation
- Operation
Applicable PlatformsLanguages
All
Common Consequences| Scope | Effect |
|---|---|
Access Control | Elevation of privilege |
Confidentiality | Information disclosure |
Integrity | Arbitrary code execution |
Likelihood of ExploitLow
Enabling Factors for ExploitationAn application contains functions running processes that hold higher privileges. |
There is code in the application that calls the privileged APIs. |
There is a way for a user to control the data that is being passed to the privileged API or control the context from which it is being called. |
Observed Examples| Reference | Description |
|---|---|
| From http://xforce.iss.net/xforce/xfdb/12848: man-db is a Unix utility that displays online help files. man-db versions 2.3.12 beta and 2.3.18 to 2.4.1 could allow a local attacker to gain privileges, caused by a vulnerability when the open cat stream function is called. If man-db is installed setuid, a local attacker could exploit this vulnerability to gain "man" user privileges. |
Potential MitigationsPhase: Implementation Before calling privileged APIs, always ensure that the assumptions made by the privileged code hold true prior to making the call. |
Know architecture and implementation weaknesses of the privileged APIs and make sure to account for these weaknesses before calling the privileged APIs to ensure that they can be called safely. |
If privileged APIs make certain assumptions about data, context or state validity that are passed by the caller, the calling code must ensure that these assumptions have been validated prior to making the call. |
If privileged APIs fail to shed their privilege prior to returning to the calling code, then calling code needs to shed these privileges immediately and safely right after the call to the privileged APIs. In particular, the calling code needs to ensure that a privileged thread of execution will never be returned to the user or made available to user-controlled processes. |
Only call privileged APIs from safe, consistent and expected state. |
Ensure that a failure or an error will not leave a system in a state where privileges are not properly shed and privilege escalation is possible (i.e. fail securely with regards to handling of privileges). |
Relationships| Nature | Type | ID | Name | View(s) this relationship pertains to |
|---|---|---|---|---|
| ChildOf |  Weakness Class | 227 | Failure to Fulfill API Contract ('API Abuse') | Research Concepts1000 |
| ChildOf |  Category | 265 | Privilege / Sandbox Issues | Development Concepts (primary)699 |
| ChildOf |  Weakness Base | 269 | Improper Privilege Management | Research Concepts (primary)1000 |
Related Attack Patterns| CAPEC-ID | Attack Pattern Name | (CAPEC Version: 1.4) |
|---|---|---|
| 107 | Cross Site Tracing |
Content History| Submissions | ||||
|---|---|---|---|---|
| Submission Date | Submitter | Organization | Source | |
| 2008-01-30 | Evgeny Lebanidze | Cigital | External Submission | |
| Modifications | ||||
| Modification Date | Modifier | Organization | Source | |
| 2008-09-08 | CWE Content Team | MITRE | Internal | |
| updated Common Consequences, Relationships | ||||
| 2008-10-14 | CWE Content Team | MITRE | Internal | |
| updated Description, Potential Mitigations | ||||
| 2009-05-27 | CWE Content Team | MITRE | Internal | |
| updated Name, Related Attack Patterns | ||||
| 2009-10-29 | CWE Content Team | MITRE | Internal | |
| updated Common Consequences | ||||
| Previous Entry Names | ||||
| Change Date | Previous Entry Name | |||
| 2009-05-27 | Improper Use of Privileged APIs | |||
