{"cveID":"CVE-2021-31207","vendorProject":"Microsoft","product":"Exchange Server","vulnerabilityName":"Microsoft Exchange Server Security Feature Bypass Vulnerability","dateAdded":"2021-11-03","shortDescription":"Microsoft Exchange Server contains an unspecified vulnerability that allows for security feature bypass.","requiredAction":"Apply updates per vendor instructions.","dueDate":"2021-11-17","knownRansomwareCampaignUse":"Known","notes":"https://nvd.nist.gov/vuln/detail/CVE-2021-31207","cwes":["CWE-20","CWE-434"],"year":2021,"state":"mapped","stale_reasons":[],"mappings":[{"domain":"enterprise","cve":"CVE-2021-31207","technique":"T1548.002","technique_name_at_mapping":"Bypass User Account Control","mapping_type":"exploitation_technique","capability_group":"feature_bypass","comments":"This vulnerability is exploited via authentication bypass, allowing the adversary to write to files.","references":["https://www.rescana.com/post/critical-analysis-of-cve-2021-31207-bypassing-security-in-microsoft-exchange-server","https://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-Remote-Code-Execution.html"],"status":"complete","source_file":"kev-07.28.2025_attack-16.1-enterprise.json","attack_version":"16.1","kev_snapshot":"07/28/2025"},{"domain":"enterprise","cve":"CVE-2021-31207","technique":"T1565","technique_name_at_mapping":"Data Manipulation","mapping_type":"primary_impact","capability_group":"feature_bypass","comments":"This vulnerability is exploited via authentication bypass, allowing the adversary to write to files.","references":["https://www.rescana.com/post/critical-analysis-of-cve-2021-31207-bypassing-security-in-microsoft-exchange-server","https://packetstormsecurity.com/files/163895/Microsoft-Exchange-ProxyShell-Remote-Code-Execution.html"],"status":"complete","source_file":"kev-07.28.2025_attack-16.1-enterprise.json","attack_version":"16.1","kev_snapshot":"07/28/2025"}],"techniques":[{"id":"T1548.002","domains":["enterprise"],"in_current_bundle":true,"live":true,"name_now":"Bypass User Account Control","name_at_mapping":"Bypass User Account Control","renamed":false,"revoked_by":null,"mapping_types":["exploitation_technique"],"sigma_rule_count":56,"has_detection_strategy":true},{"id":"T1565","domains":["enterprise"],"in_current_bundle":true,"live":true,"name_now":"Data Manipulation","name_at_mapping":"Data Manipulation","renamed":false,"revoked_by":null,"mapping_types":["primary_impact"],"sigma_rule_count":3,"has_detection_strategy":true}],"mapping_types":["exploitation_technique","primary_impact"],"has_exploitation_technique":true,"mapping_attack_versions":["16.1"],"mapping_domains":["enterprise"],"sigma_coverage":"full","sigma_rules_tagged_cve":[],"added_after_mapping_snapshot":false,"_source":"kevmap","_built":"2026-08-23 05:47 UTC","_attack_version":"19.2"}