{"cve":{"cve_id":"CVE-2021-30858","is_kev":true,"kev_date_added":"2021-11-03","kev_vendor_project":"Apple","kev_product":"iOS, iPadOS, and macOS","kev_vulnerability_name":"Apple iOS, iPadOS, macOS Use-After-Free Vulnerability","kev_short_description":"Apple iOS, iPadOS, and macOS WebKit contain a use-after-free vulnerability that leads to code execution when processing maliciously crafted web content. This vulnerability could impact HTML parsers that use WebKit, including but not limited to Apple Safari and non-Apple products which rely on WebKit for HTML processing.","kev_required_action":"Apply updates per vendor instructions.","kev_due_date":"2021-11-17","kev_known_ransomware":false,"kev_notes":"https://nvd.nist.gov/vuln/detail/CVE-2021-30858","kev_cwes":["CWE-416"],"epss_score":0.13486,"epss_percentile":0.95951,"epss_as_of":"2026-06-23","description":"A use after free issue was addressed with improved memory management. This issue is fixed in iOS 14.8 and iPadOS 14.8, macOS Big Sur 11.6. Processing maliciously crafted web content may lead to arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited.","published_at":"2021-08-24T18:49:23Z","last_modified_at":null,"cvss_v3_score":8.8,"cvss_v3_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","cvss_v3_severity":"HIGH","cvss_v4_score":null,"cvss_v4_vector":null,"cvss_v4_severity":null,"ssvc_decision":null,"ssvc_exploitation":"active","ssvc_automatable":false,"ssvc_technical_impact":"total","cwes":["CWE-416"],"nvd_references":["https://support.apple.com/en-us/HT212804","https://support.apple.com/en-us/HT212807","http://seclists.org/fulldisclosure/2021/Sep/27","http://seclists.org/fulldisclosure/2021/Sep/25","http://seclists.org/fulldisclosure/2021/Sep/29","http://www.openwall.com/lists/oss-security/2021/09/20/1","https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BO6DMTHZR57JDBOXPSNR2MKDMCRWV265/","http://seclists.org/fulldisclosure/2021/Sep/38","http://seclists.org/fulldisclosure/2021/Sep/39","https://www.debian.org/security/2021/dsa-4975","https://www.debian.org/security/2021/dsa-4976","https://support.apple.com/kb/HT212824","http://seclists.org/fulldisclosure/2021/Sep/50","https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XYNV7ASK4LQVAUMJXNXBS3Z7RVDQ2N3W/","http://www.openwall.com/lists/oss-security/2021/10/26/9","http://www.openwall.com/lists/oss-security/2021/10/27/1","http://www.openwall.com/lists/oss-security/2021/10/27/2","http://www.openwall.com/lists/oss-security/2021/10/27/4"],"vuln_status":null,"trending_score":null,"is_trending":false,"has_trended":false,"trended_number_one":false,"trending_peak_score":null,"trending_peak_rank":null,"started_trending_at":null,"trended_number_one_at":null,"summary_generated":null,"summary_generated_at":null,"summary_model":null,"created_at":"2026-06-24T00:09:31.350578Z","updated_at":"2026-06-28T23:15:33.821234Z"},"effective_severity":"HIGH","badges":["kev"],"impact_analysis":[],"cvss_v3_decoded":{"version":"3.1","metrics":[{"metric":"AV","name":"Attack Vector","value":"N","value_label":"Network"},{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"PR","name":"Privileges Required","value":"N","value_label":"None"},{"metric":"UI","name":"User Interaction","value":"R","value_label":"Required"},{"metric":"S","name":"Scope","value":"U","value_label":"Unchanged"},{"metric":"C","name":"Confidentiality","value":"H","value_label":"High"},{"metric":"I","name":"Integrity","value":"H","value_label":"High"},{"metric":"A","name":"Availability","value":"H","value_label":"High"}]},"cvss_v4_decoded":{"version":null,"metrics":[]},"affected":[{"vendor_slug":"apple","vendor_name":"Apple","product_slug":"ios","product_name":"iOS","version_start":"unspecified","version_start_inclusive":true,"version_end":"14.8","version_end_inclusive":false,"cpe23_uri":"cve5:apple:ios:unspecified:14.8"},{"vendor_slug":"apple","vendor_name":"Apple","product_slug":"macos","product_name":"macOS","version_start":"unspecified","version_start_inclusive":true,"version_end":"11.6","version_end_inclusive":false,"cpe23_uri":"cve5:apple:macos:unspecified:11.6"}],"exploit_refs":[],"news":[],"references":[{"url":"https://support.apple.com/en-us/HT212804","source_type":"VENDOR_ADVISORY","tags":["advisory"]},{"url":"https://support.apple.com/en-us/HT212807","source_type":"VENDOR_ADVISORY","tags":["advisory"]},{"url":"http://seclists.org/fulldisclosure/2021/Sep/27","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"http://seclists.org/fulldisclosure/2021/Sep/25","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"http://seclists.org/fulldisclosure/2021/Sep/29","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"http://www.openwall.com/lists/oss-security/2021/09/20/1","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BO6DMTHZR57JDBOXPSNR2MKDMCRWV265/","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"http://seclists.org/fulldisclosure/2021/Sep/38","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"http://seclists.org/fulldisclosure/2021/Sep/39","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"https://www.debian.org/security/2021/dsa-4975","source_type":"VENDOR_ADVISORY","tags":["advisory"]},{"url":"https://www.debian.org/security/2021/dsa-4976","source_type":"VENDOR_ADVISORY","tags":["advisory"]},{"url":"https://support.apple.com/kb/HT212824","source_type":"VENDOR_ADVISORY","tags":["advisory"]},{"url":"http://seclists.org/fulldisclosure/2021/Sep/50","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XYNV7ASK4LQVAUMJXNXBS3Z7RVDQ2N3W/","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"http://www.openwall.com/lists/oss-security/2021/10/26/9","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"http://www.openwall.com/lists/oss-security/2021/10/27/1","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"http://www.openwall.com/lists/oss-security/2021/10/27/2","source_type":"MAILING_LIST","tags":["mailing-list"]},{"url":"http://www.openwall.com/lists/oss-security/2021/10/27/4","source_type":"MAILING_LIST","tags":["mailing-list"]}],"timeline":[{"type":"published","at":"2021-08-24T18:49:23Z","label":"CVE published","source":null},{"type":"cisa_reported","at":"2021-11-03T00:00:00Z","label":"Added to CISA KEV catalog","source":"kev"},{"type":"ssvc_changed","at":"2026-06-24T00:31:42.220317Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-06-24T00:31:42.220317Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"ssvc_changed","at":"2026-06-24T00:31:42.220317Z","label":"SSVC decision revised","source":"vulnrichment"},{"type":"cvss_changed","at":"2026-06-24T00:31:42.220317Z","label":"CVSS score revised","source":"vulnrichment"},{"type":"cvss_changed","at":"2026-06-24T00:31:42.220317Z","label":"CVSS score revised","source":"vulnrichment"},{"type":"cvss_changed","at":"2026-06-24T00:31:42.220317Z","label":"CVSS score revised","source":"vulnrichment"}]}