CWE-209: Generation of Error Message Containing Sensitive Information

Description

The product generates an error message that includes sensitive information about its environment, users, or associated data.

Abstraction: BaseA weakness specific enough to point to detection and prevention methods.
Likelihood of exploit: High
Status: Draft

Common consequences

Confidentiality
Read Application Data
Often this will either reveal sensitive information which may be used to launch another, more focused attack or disclose private information stored in the server. For example, an attempt to exploit a path traversal weakness (CWE-22) might yield the full pathname of the installed application. In turn, this could be used...

Potential mitigations

Implementation
Ensure that error messages only contain minimal details that are useful to the intended audience and no one else. The messages need to strike the balance between being too cryptic (which can confuse users) or being too detailed (which may reveal more than intended). The messages should not reveal the methods that were used to determine the error. Attackers can use detailed information to refine or optimize their original attack, thereby increasing their chances of success. If errors must be captured in some detail, record them in log messages, but consider what could occur if the log messages...
Implementation
Handle exceptions internally and do not display errors containing potentially sensitive information to a user.
ImplementationAttack Surface ReductionEffectiveness: Defense in Depth
Use naming conventions and strong types to make it easier to spot when sensitive data is being used. When creating structures, objects, or other complex entities, separate the sensitive and non-sensitive data as much as possible.
ImplementationBuild and CompilationCompilation or Build Hardening
Debugging information should not make its way into a production release.
ImplementationBuild and CompilationEnvironment Hardening
Debugging information should not make its way into a production release.
System Configuration
Where available, configure the environment to use less verbose error messages. For example, in PHP, disable the display_errors setting during configuration, or at runtime using the error_reporting() function.
System Configuration
Create default error pages or messages that do not leak any information.

Related weaknesses

Parent weaknesses

Child weaknesses

CAPEC attack patterns that exploit it

Common consequences

Confidentiality

Read Application Data

Often this will either reveal sensitive information which may be used to launch another, more focused attack or disclose private information stored in the server. For example, an attempt to exploit a path traversal weakness (CWE-22) might yield the full pathname of the installed application. In turn, this could be used...

Potential mitigations

Implementation

Ensure that error messages only contain minimal details that are useful to the intended audience and no one else. The messages need to strike the balance between being too cryptic (which can confuse users) or being too detailed (which may reveal more than intended). The messages should not reveal the methods that were used to determine the error. Attackers can use detailed information to refine or optimize their original attack, thereby increasing their chances of success. If errors must be captured in some detail, record them in log messages, but consider what could occur if the log messages...

Implementation

Handle exceptions internally and do not display errors containing potentially sensitive information to a user.

ImplementationAttack Surface ReductionEffectiveness: Defense in Depth

Use naming conventions and strong types to make it easier to spot when sensitive data is being used. When creating structures, objects, or other complex entities, separate the sensitive and non-sensitive data as much as possible.

ImplementationBuild and CompilationCompilation or Build Hardening

Debugging information should not make its way into a production release.

ImplementationBuild and CompilationEnvironment Hardening

Debugging information should not make its way into a production release.

System Configuration

Where available, configure the environment to use less verbose error messages. For example, in PHP, disable the display_errors setting during configuration, or at runtime using the error_reporting() function.

System Configuration

Create default error pages or messages that do not leak any information.