{"@ID": "638", "@Name": "Not Using Complete Mediation", "@Abstraction": "Class", "@Structure": "Simple", "@Status": "Draft", "Description": "The product does not perform access checks on a resource every time the resource is accessed by an entity, which can create resultant weaknesses if that entity's rights or privileges change over time.", "Related_Weaknesses": {"Related_Weakness": [{"@Nature": "ChildOf", "@CWE_ID": "657", "@View_ID": "1000", "@Ordinal": "Primary"}, {"@Nature": "ChildOf", "@CWE_ID": "862", "@View_ID": "1000"}]}, "Weakness_Ordinalities": {"Weakness_Ordinality": {"Ordinality": "Primary"}}, "Applicable_Platforms": {"Language": {"@Class": "Not Language-Specific", "@Prevalence": "Undetermined"}}, "Modes_Of_Introduction": {"Introduction": [{"Phase": "Implementation"}, {"Phase": "Operation"}]}, "Common_Consequences": {"Consequence": {"Scope": ["Integrity", "Confidentiality", "Availability", "Access Control", "Other"], "Impact": ["Gain Privileges or Assume Identity", "Execute Unauthorized Code or Commands", "Bypass Protection Mechanism", "Read Application Data", "Other"], "Note": "A user might retain access to a critical resource even after privileges have been revoked, possibly allowing access to privileged functionality or sensitive information, depending on the role of the resource."}}, "Potential_Mitigations": {"Mitigation": [{"Phase": "Architecture and Design", "Description": "Invalidate cached privileges, file handles or descriptors, or other access credentials whenever identities, processes, policies, roles, capabilities or permissions change. Perform complete authentication checks before accepting, caching and reusing data, dynamic content and code (scripts). Avoid caching access control decisions as much as possible."}, {"Phase": "Architecture and Design", "Description": "Identify all possible code paths that might access sensitive resources. If possible, create and use a single interface that performs the access checks, and develop code standards that require use of this interface."}]}, "Demonstrative_Examples": {"Demonstrative_Example": [{"@Demonstrative_Example_ID": "DX-166", "Intro_Text": "When executable library files are used on web servers, which is common in PHP applications, the developer might perform an access check in any user-facing executable, and omit the access check from the library file itself. By directly requesting the library file (CWE-425), an attacker can bypass this access check."}, {"Intro_Text": "When a developer begins to implement input validation for a web application, often the validation is performed in each area of the code that uses externally-controlled input. In complex applications with many inputs, the developer often misses a parameter here or a cookie there. One frequently-applied solution is to centralize all input validation, store these validated inputs in a separate data structure, and require that all access of those inputs must be through that data structure. An alternate approach would be to use an external input validation framework such as Struts, which performs the validation before the inputs are ever processed by the code."}]}, "Observed_Examples": {"Observed_Example": {"Reference": "CVE-2007-0408", "Description": "Server does not properly validate client certificates when reusing cached connections.", "Link": "https://www.cve.org/CVERecord?id=CVE-2007-0408"}}, "Taxonomy_Mappings": {"Taxonomy_Mapping": {"@Taxonomy_Name": "Software Fault Patterns", "Entry_ID": "SFP20", "Entry_Name": "Race Condition Window"}}, "Related_Attack_Patterns": {"Related_Attack_Pattern": {"@CAPEC_ID": "104"}}, "References": {"Reference": [{"@External_Reference_ID": "REF-196"}, {"@External_Reference_ID": "REF-526"}]}, "Mapping_Notes": {"Usage": "Allowed-with-Review", "Rationale": "This CWE entry is a Class and might have Base-level children that would be more appropriate", "Comments": "Examine children of this entry to see if there is a better fit", "Reasons": {"Reason": {"@Type": "Abstraction"}}}, "Content_History": {"Submission": {"Submission_Name": "Pascal Meunier", "Submission_Organization": "Purdue University", "Submission_Date": "2008-01-18", "Submission_Version": "Draft 8", "Submission_ReleaseDate": "2008-01-30"}, "Modification": [{"Modification_Name": "Eric Dalci", "Modification_Organization": "Cigital", "Modification_Date": "2008-07-01", "Modification_Version": "1.0", "Modification_ReleaseDate": "2008-09-09", "Modification_Comment": "updated Time_of_Introduction"}, {"Modification_Name": "CWE Content Team", "Modification_Organization": "MITRE", "Modification_Date": "2008-09-08", "Modification_Version": "1.0", "Modification_ReleaseDate": "2008-09-09", "Modification_Comment": "updated Common_Consequences, Relationships, Observed_Example, Weakness_Ordinalities"}, {"Modification_Name": "CWE Content Team", "Modification_Organization": "MITRE", "Modification_Date": "2009-01-12", "Modification_Version": "1.2", "Modification_ReleaseDate": "2009-01-12", "Modification_Comment": "updated Description, Name"}, {"Modification_Name": "CWE Content Team", "Modification_Organization": "MITRE", "Modification_Date": "2009-05-27", "Modification_Version": "1.4", "Modification_ReleaseDate": "2009-05-27", "Modification_Comment": "updated Related_Attack_Patterns"}, {"Modification_Name": "CWE Content Team", "Modification_Organization": "MITRE", "Modification_Date": "2010-12-13", "Modification_Version": "1.11", "Modification_ReleaseDate": "2010-12-13", "Modification_Comment": "updated Name"}, {"Modification_Name": "CWE Content Team", "Modification_Organization": "MITRE", "Modification_Date": "2011-06-01", "Modification_Version": "1.13", "Modification_ReleaseDate": "2011-06-01", "Modification_Comment": "updated Common_Consequences, Relationships"}, {"Modification_Name": "CWE Content Team", "Modification_Organization": "MITRE", "Modification_Date": "2012-05-11", "Modification_Version": "2.2", "Modification_ReleaseDate": "2012-05-15", "Modification_Comment": "updated Relationships"}, {"Modification_Name": "CWE Content Team", "Modification_Organization": "MITRE", "Modification_Date": "2012-10-30", "Modification_Version": "2.3", "Modification_ReleaseDate": "2012-10-30", "Modification_Comment": "updated Potential_Mitigations"}, {"Modification_Name": "CWE Content Team", "Modification_Organization": "MITRE", "Modification_Date": "2014-07-30", "Modification_Version": "2.8", "Modification_ReleaseDate": "2014-07-31", "Modification_Comment": "updated Relationships, Taxonomy_Mappings"}, {"Modification_Name": "CWE Content Team", "Modification_Organization": "MITRE", "Modification_Date": "2017-11-08", "Modification_Version": "3.0", "Modification_ReleaseDate": "2017-11-08", "Modification_Comment": "updated Applicable_Platforms, Causal_Nature"}, {"Modification_Name": "CWE Content Team", "Modification_Organization": "MITRE", "Modification_Date": "2020-02-24", "Modification_Version": "4.0", "Modification_ReleaseDate": "2020-02-24", "Modification_Comment": "updated Relationships"}, {"Modification_Name": "CWE Content Team", "Modification_Organization": "MITRE", "Modification_Date": "2022-10-13", "Modification_Version": "4.9", "Modification_ReleaseDate": "2022-10-13", "Modification_Comment": "updated References"}, {"Modification_Name": "CWE Content Team", "Modification_Organization": "MITRE", "Modification_Date": "2023-01-31", "Modification_Version": "4.10", "Modification_ReleaseDate": "2023-01-31", "Modification_Comment": "updated Description, Relationships"}, {"Modification_Name": "CWE Content Team", "Modification_Organization": "MITRE", "Modification_Date": "2023-04-27", "Modification_Version": "4.11", "Modification_ReleaseDate": "2023-04-27", "Modification_Comment": "updated References, Relationships, Time_of_Introduction"}, {"Modification_Name": "CWE Content Team", "Modification_Organization": "MITRE", "Modification_Date": "2023-06-29", "Modification_Version": "4.12", "Modification_ReleaseDate": "2023-06-29", "Modification_Comment": "updated Mapping_Notes"}, {"Modification_Name": "CWE Content Team", "Modification_Organization": "MITRE", "Modification_Date": "2023-10-26", "Modification_Version": "4.13", "Modification_ReleaseDate": "2023-10-26", "Modification_Comment": "updated Demonstrative_Examples"}], "Previous_Entry_Name": [{"@Date": "2009-01-12", "#text": "Design Principle Violation: Not Using Complete Mediation"}, {"@Date": "2010-12-13", "#text": "Failure to Use Complete Mediation"}]}}