{"@ID": "325", "@Name": "Missing Cryptographic Step", "@Abstraction": "Base", "@Structure": "Simple", "@Status": "Draft", "Description": "The product does not implement a required step in a cryptographic algorithm, resulting in weaker encryption than advertised by the algorithm.", "Related_Weaknesses": {"Related_Weakness": [{"@Nature": "ChildOf", "@CWE_ID": "1240", "@View_ID": "1000", "@Ordinal": "Primary"}, {"@Nature": "ChildOf", "@CWE_ID": "573", "@View_ID": "1000"}, {"@Nature": "PeerOf", "@CWE_ID": "358", "@View_ID": "1000"}]}, "Weakness_Ordinalities": {"Weakness_Ordinality": {"Ordinality": "Primary"}}, "Applicable_Platforms": {"Language": {"@Class": "Not Language-Specific", "@Prevalence": "Undetermined"}, "Technology": {"@Class": "Not Technology-Specific", "@Prevalence": "Undetermined"}}, "Modes_Of_Introduction": {"Introduction": [{"Phase": "Implementation", "Note": "Developers sometimes omit \"expensive\" (resource-intensive) steps in order to improve performance, especially in devices with limited memory or slower CPUs. This step may be taken under a mistaken impression that the step is unnecessary for the cryptographic algorithm."}, {"Phase": "Requirements", "Note": "This issue may happen when the requirements for the cryptographic algorithm are not clearly stated."}]}, "Common_Consequences": {"Consequence": [{"Scope": "Access Control", "Impact": "Bypass Protection Mechanism"}, {"Scope": ["Confidentiality", "Integrity"], "Impact": ["Read Application Data", "Modify Application Data"]}, {"Scope": ["Accountability", "Non-Repudiation"], "Impact": "Hide Activities"}]}, "Detection_Methods": {"Detection_Method": {"@Detection_Method_ID": "DM-14", "Method": "Automated Static Analysis", "Description": "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.)"}}, "Demonstrative_Examples": {"Demonstrative_Example": {"Intro_Text": "The example code is taken from the HMAC engine inside the buggy OpenPiton SoC of HACK@DAC'21 [REF-1358]. HAMC is a message authentication code (MAC) that uses both a hash and a secret crypto key. The HMAC engine in HACK@DAC SoC uses the SHA-256 module for the calculation of the HMAC for 512 bits messages.", "Example_Code": {"@Nature": "Bad", "@Language": "Verilog", "xhtml:b": "logic [511:0] bigData;", "xhtml:br": [null, null, null, null], "xhtml:div": {"@style": "margin-left:1em;", "xhtml:br": [null, null, null, null, null, null, null, null, null, null, null], "xhtml:b": ".message_i(bigData),", "#text": ".clk_i(clk_i),\n                  .rst_ni(rst_ni && ~rst_4),\n                  .init_i(startHash && ~startHash_r),\n                  .key_i(key),\n                  .ikey_hash_i(ikey_hash), \n                  .okey_hash_i(okey_hash), \n                  .key_hash_bypass_i(key_hash_bypass),\n                  \n                  .hash_o(hash),\n                  .ready_o(ready),\n                  .hash_valid_o(hashValid)"}, "#text": "...\n               \n               hmac hmac("}, "Body_Text": ["However, this HMAC engine cannot handle messages that are longer than 512 bits. Moreover, a complete HMAC will contain an iterate hash function that breaks up a message into blocks of a fixed size and iterates over them with a compression function (e.g., SHA-256). Therefore, the implementation of the HMAC in OpenPiton SoC is incomplete. Such HMAC engines will not be used in real-world applications as the messages will usually be longer than 512 bits. For instance, OpenTitan offers a comprehensive HMAC implementation that utilizes a FIFO for temporarily storing the truncated message, as detailed in [REF-1359].", "To mitigate this, implement the iterative function to break up a message into blocks of a fixed size."]}}, "Observed_Examples": {"Observed_Example": {"Reference": "CVE-2001-1585", "Description": "Missing challenge-response step allows authentication bypass using public key.", "Link": "https://www.cve.org/CVERecord?id=CVE-2001-1585"}}, "Functional_Areas": {"Functional_Area": "Cryptography"}, "Taxonomy_Mappings": {"Taxonomy_Mapping": [{"@Taxonomy_Name": "PLOVER", "Entry_Name": "Missing Required Cryptographic Step"}, {"@Taxonomy_Name": "OWASP Top Ten 2007", "Entry_ID": "A8", "Entry_Name": "Insecure Cryptographic Storage", "Mapping_Fit": "CWE More Specific"}, {"@Taxonomy_Name": "OWASP Top Ten 2007", "Entry_ID": "A9", "Entry_Name": "Insecure Communications", "Mapping_Fit": "CWE More Specific"}]}, "Related_Attack_Patterns": {"Related_Attack_Pattern": {"@CAPEC_ID": "68"}}, "References": {"Reference": [{"@External_Reference_ID": "REF-1358"}, {"@External_Reference_ID": "REF-1359"}]}, "Mapping_Notes": {"Usage": "Allowed", "Rationale": "This CWE entry is at the Base level of abstraction, which is a preferred level of abstraction for mapping to the root causes of vulnerabilities.", "Comments": "Carefully read both the name and description to ensure that this mapping is an appropriate fit. Do not try to 'force' a mapping to a lower-level Base/Variant simply to comply with this preferred level of abstraction.", "Reasons": {"Reason": {"@Type": "Acceptable-Use"}}}, "Notes": {"Note": [{"@Type": "Relationship", "#text": "Overlaps incomplete/missing security check."}, {"@Type": "Relationship", "#text": "Can be resultant."}]}, "Content_History": {"Submission": {"Submission_Name": "PLOVER", "Submission_Date": "2006-07-19", "Submission_Version": "Draft 3", "Submission_ReleaseDate": "2006-07-19"}, "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 Description, Functional_Areas, Modes_of_Introduction, Relationships, Observed_Example, Relationship_Notes, Taxonomy_Mappings"}, {"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"}, {"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 Common_Consequences, Relationships"}, {"Modification_Name": "CWE Content Team", "Modification_Organization": "MITRE", "Modification_Date": "2014-06-23", "Modification_Version": "2.7", "Modification_ReleaseDate": "2014-06-23", "Modification_Comment": "updated Relationships"}, {"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"}, {"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, Modes_of_Introduction, Relationships"}, {"Modification_Name": "CWE Content Team", "Modification_Organization": "MITRE", "Modification_Date": "2018-03-27", "Modification_Version": "3.1", "Modification_ReleaseDate": "2018-03-27", "Modification_Comment": "updated Relationships"}, {"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 Applicable_Platforms, Description, Relationships"}, {"Modification_Name": "CWE Content Team", "Modification_Organization": "MITRE", "Modification_Date": "2020-08-20", "Modification_Version": "4.2", "Modification_ReleaseDate": "2020-08-20", "Modification_Comment": "updated Common_Consequences, Description, Modes_of_Introduction, Name"}, {"Modification_Name": "CWE Content Team", "Modification_Organization": "MITRE", "Modification_Date": "2021-10-28", "Modification_Version": "4.6", "Modification_ReleaseDate": "2021-10-28", "Modification_Comment": "updated 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 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, References"}, {"Modification_Name": "CWE Content Team", "Modification_Organization": "MITRE", "Modification_Date": "2025-12-11", "Modification_Version": "4.19", "Modification_ReleaseDate": "2025-12-11", "Modification_Comment": "updated Detection_Factors, Relationships, Weakness_Ordinalities"}], "Contribution": [{"@Type": "Content", "Contribution_Name": "Chen Chen, Rahul Kande, Jeyavijayan Rajendran", "Contribution_Organization": "Texas A&M University", "Contribution_Date": "2023-06-21", "Contribution_Comment": "suggested demonstrative example"}, {"@Type": "Content", "Contribution_Name": "Shaza Zeitouni, Mohamadreza Rostami, Ahmad-Reza Sadeghi", "Contribution_Organization": "Technical University of Darmstadt", "Contribution_Date": "2023-06-21", "Contribution_Comment": "suggested demonstrative example"}], "Previous_Entry_Name": {"@Date": "2020-08-20", "#text": "Missing Required Cryptographic Step"}}}