Description
A covert storage channel transfers information through the setting of bits by one program and the reading of those bits by another. What distinguishes this case from that of ordinary operation is that the bits are used to convey encoded information.
Covert storage channels occur when out-of-band data is stored in messages for the purpose of memory reuse. Covert channels are frequently classified as either storage or timing channels. Examples would include using a file intended to hold only audit information to convey user passwords--using the name of a file or perhaps status bits associated with it that can be read by all users to signal the contents of the file. Steganography, concealing information in such a manner that no one but the intended recipient knows of the existence of the message, is a good example of a covert storage channel.
Potential Impact
Confidentiality
Read Application Data
Integrity, Confidentiality
Read Application Data
Mitigations & Prevention
Ensure that all reserved fields are set to zero before messages are sent and that no unnecessary information is included.
Related Weaknesses
Taxonomy Mappings
- Landwehr: — Storage
- CLASP: — Covert storage channel
Frequently Asked Questions
What is CWE-515?
CWE-515 (Covert Storage Channel) is a software weakness identified by MITRE's Common Weakness Enumeration. It is classified as a Base-level weakness. A covert storage channel transfers information through the setting of bits by one program and the reading of those bits by another. What distinguishes this case from that of ordinary operation is that...
How can CWE-515 be exploited?
Attackers can exploit CWE-515 (Covert Storage Channel) to read application data. This weakness is typically introduced during the Implementation phase of software development.
How do I prevent CWE-515?
Key mitigations include: Ensure that all reserved fields are set to zero before messages are sent and that no unnecessary information is included.
What is the severity of CWE-515?
CWE-515 is classified as a Base-level weakness (Medium abstraction). Its actual severity depends on the specific context and how the weakness manifests in your application.