CWE-515: Covert Storage Channel
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.
View on MITREExtended Description
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.
Technical Details
- Structure
- Simple
Applicable To
Security Consequences
Scope
Impact
Covert storage channels may provide attackers with important information about the system in question.
Scope
Impact
If these messages or packets are sent with unnecessary data contained within, it may tip off malicious listeners as to the process that created the message. With this information, attackers may learn any number of things, including the hardware platform, operating system, or algorithms used by the sender. This information can be of significant value to the user in launching further attacks.
Mitigation Strategies
Phase
Description
Ensure that all reserved fields are set to zero before messages are sent and that no unnecessary information is included.
Detection Methods
No detection method information available for this CWE.
Code Examples & CVEs
No examples or observed CVEs available for this CWE.
CWE Relationships
Frequently Asked Questions
What is CWE-515: Covert Storage Channel?+
CWE-515: Covert Storage Channel is a Common Weakness Enumeration (CWE) entry maintained by MITRE. 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.
What are the security consequences of Covert Storage Channel?+
If exploited, CWE-515 (Covert Storage Channel) it can compromise Confidentiality and Integrity, leading to outcomes such as Read Application Data.
How do you prevent or mitigate Covert Storage Channel?+
Recommended mitigations for CWE-515 include: Ensure that all reserved fields are set to zero before messages are sent and that no unnecessary information is included.
What is the difference between a CWE and a CVE?+
A CWE (Common Weakness Enumeration) like CWE-515 describes a category of software weakness — the underlying flaw type. A CVE (Common Vulnerabilities and Exposures) identifies a specific, real-world vulnerability in a particular product. In short, a CWE is the kind of mistake, and a CVE is an instance of that mistake being found in software.