CWE-603: Use of Client-Side Authentication
Official CWE-603 CWE context with Glexia analysis, remediation guidance, related CVEs, and ATT&CK context.
Glexia's Take
CWE-603: Use of Client-Side Authentication
Use of Client-Side Authentication represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
Executive Impact
- Access Control: Bypass Protection Mechanism,Gain Privileges or Assume Identity
Developer Pattern
CWE-603 is the kind of defect developers can usually prevent with explicit validation, safer framework defaults, and tests that exercise hostile input or unsafe state transitions.
Confidence
high confidence from CWE-603, 4.20.
Official CWE Definition
CWE-603: Use of Client-Side Authentication
A client/server product performs authentication within client code but not in server code, allowing server-side authentication to be bypassed via a modified client that omits the authentication check.
Client-side authentication is extremely weak and may be breached easily. Any attacker may read the source code and reverse-engineer the authentication mechanism to access parts of the application which would otherwise be protected.
Developer And Remediation Guidance
How teams prevent and detect this weakness
Causes
- In 2022, the OT:ICEFALL study examined products by 10 different Operational Technology (OT) vendors. The researchers reported 56 vulnerabilities and said that the products were "insecure by design" [REF-1283]. If exploited, these vulnerabilities often allowed adversaries to change how the products operated, ranging from denial of service to changing the code that the products executed. Since these products were often used in industries such as power, electrical, water, and others, there could even be safety implications. Multiple vendors used client-side authentication in their OT products.
Remediation
- Architecture and Design: Do not rely on client side data. Always perform server side authentication.
Detection
- Code review
- SAST
- DAST
- Focused regression tests
Mappings
Related CVEs, CWEs, and ATT&CK context
Related CWEs
ATT&CK Relevance
ATT&CK relevance is shown only when reviewed or responsibly inferred.