CWE-321

Variant Abstraction Level
Pillar — Highest-level weakness category
Class — Abstract, language-independent
Base — Specific enough to detect
Variant — Tied to specific technology
Compound — Requires multiple weaknesses Draft MITRE CWE Status
Stable — Fully reviewed and complete
Draft — Under development, may change
Incomplete — Partially defined by MITRE
Deprecated — No longer recommended
Obsolete — Replaced by another CWE Exploit: High
Use of Hard-coded Cryptographic Key

Description

The product uses a hard-coded, unchangeable cryptographic key.

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Consequences

Access Control — Bypass Protection Mechanism, Gain Privileges or Assume Identity, Read Application Data

If hard-coded cryptographic keys are used, it is almost certain that malicious users will gain access through the account in question. The use of a hard-coded cryptographic key significantly increases the possibility that encrypted data may be recovered.

Mitigations

Phase: Architecture and Design

Prevention schemes mirror that of hard-coded password storage.

Detection

Automated Static Analysis

Automated static analysis, commonly referred to as Static Application Security Testing (SAST), can find some instances of this weakness by analyzing source code (or binary/compiled code) without having to execute it. Typically, this is done by building a model of data flow and control flow, then searching for potentially-vulnerable patterns that connect "sources" (origins of input) with "sinks" (destinations where the data interacts with external components, a lower layer such as the OS, etc.)