CWE-201: Insertion of Sensitive Information Into Sent Data
The code transmits data to another actor, but a portion of the data includes sensitive information that should not be accessible to that actor.
How it's found
Insertion of Sensitive Information Into Sent Data is typically found by tracing untrusted input from where it enters the system to the point where it is used without the check or neutralization this weakness describes, combining manual code review with dynamic testing.
Consequences
- Read Files or Directories, Read Memory, Read Application Data: Sensitive data may be exposed to attackers.
Mitigations
- Requirements: Specify which data in the software should be regarded as sensitive. Consider which types of users should have access to which types of data.
- Implementation: Ensure that any possibly sensitive data specified in the requirements is verified with designers to ensure that it is either a calculated risk or mitigated elsewhere. Any information that is not necessary to the functionality should be removed in order to lower both the overhead and the possibility of security sensitive data being sent.
- System Configuration: Setup default error messages so that unexpected errors do not disclose sensitive information.
- Architecture and Design: 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.
Where this fits in a TurboPentest engagement
This weakness is not covered by the automated black-box pentest. IntegSec pentesters cover it in a manual engagement.
Frequently asked questions
What is CWE-201?
The code transmits data to another actor, but a portion of the data includes sensitive information that should not be accessible to that actor.
How do you find Insertion of Sensitive Information Into Sent Data?
Insertion of Sensitive Information Into Sent Data is typically found by tracing untrusted input from where it enters the system to the point where it is used without the check or neutralization this weakness describes, combining manual code review with dynamic testing.
What is the impact of CWE-201?
Read Files or Directories, Read Memory, Read Application Data: Sensitive data may be exposed to attackers.
Does TurboPentest test for Insertion of Sensitive Information Into Sent Data?
This weakness is not covered by the automated black-box pentest. IntegSec pentesters cover it in a manual engagement.
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Written and reviewed by
Michel Chamberland - Founder & CEO, IntegSec
CISSP, OSCP, OSCE, CEH, GIAC, CCSK · 20+ years in offensive security
Michel has spent 20+ years on offensive security teams including IBM X-Force Red and Trustwave SpiderLabs, leading penetration tests, red team engagements, and breach response for Fortune 500 customers. He is the founder of IntegSec and the architect of TurboPentest.
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