CWE-692: Incomplete Denylist to Cross-Site Scripting | Glexia
CWE-692 (Incomplete Denylist to Cross-Site Scripting) weakness overview with consequences, detection methods, mitigations, related CVEs and MITRE ATT&CK context.
Glexia's Take · Automated analysis
CWE-692: Incomplete Denylist to Cross-Site Scripting
Incomplete Denylist to Cross-Site Scripting represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
Executive Impact
- Confidentiality Integrity Availability: Execute Unauthorized Code or Commands
Developer Pattern
CWE-692 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.
Automation confidence
high confidence from CWE-692, 4.20.
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Official CWE Definition
CWE-692: Incomplete Denylist to Cross-Site Scripting
The product uses a denylist-based protection mechanism to defend against XSS attacks, but the denylist is incomplete, allowing XSS variants to succeed.
While XSS might seem simple to prevent, web browsers vary so widely in how they parse web pages, that a denylist cannot keep track of all the variations. The "XSS Cheat Sheet" [REF-714] contains a large number of attacks that are intended to bypass incomplete denylists.
Developer And Remediation Guidance
How teams prevent and detect this weakness
Causes
- Missing validation
- Unsafe defaults
- Insufficient authorization or memory-safety invariant
Remediation
- Use safe APIs
- Centralize the control
- Add regression tests
- Review logs and telemetry for attempted abuse
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.