{"id":"CVE-2021-30858","published":"2021-08-24T19:15:14Z","modified":"2026-06-17T03:51:01Z","title":"Apple iOS, iPadOS, macOS Use-After-Free Vulnerability","vendor":"Apple","product":"iOS, iPadOS, and macOS","tier":"core","eol":null,"description":{"text":"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.","provenance":"source","from":"NVD"},"summary":{"text":"A use-after-free memory flaw in Apple's iOS, iPadOS, and macOS allows an attacker to run arbitrary code on the affected device. The attacker needs to get a victim to process maliciously crafted web content over the network, and the victim must take an action to trigger it, with no prior authentication required.","provenance":"ai","model":"claude-haiku-5-5","generatedAt":"2026-10-23T07:12:52Z"},"cvss":{"score":8.8,"severity":"HIGH","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","provenance":"source","from":"NVD"},"epss":{"score":0.13379,"percentile":0.9641,"date":"2026-10-29","provenance":"source"},"kev":{"dateAdded":"2021-11-03","dueDate":"2021-11-17","ransomware":false,"requiredAction":"Apply updates per vendor instructions.","notes":"https://nvd.nist.gov/vuln/detail/CVE-2021-30858","provenance":"source"},"vulncheckKev":{"dateAdded":"2021-09-13","exploitedFirstSeen":"2021-09-13","ransomware":false,"evidence":[{"url":"https://docs.google.com/spreadsheets/d/1lkNJ0uQwbeC1ZTRrxdtuPLCIl7mlUreoKfSIgajnSyY/edit","date":"2021-09-13"},{"url":"https://support.apple.com/en-us/103147","date":"2021-09-13"},{"url":"https://support.apple.com/en-us/103151","date":"2021-09-13"},{"url":"https://support.apple.com/kb/HT212807","date":"2021-09-13"},{"url":"https://support.apple.com/en-us/103157","date":"2021-09-23"},{"url":"https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json","date":"2021-11-03"},{"url":"https://intel471.com/blog/macos-is-increasingly-targeted-by-threat-actors","date":"2024-08-12"}],"evidenceTotal":7,"provenance":"source"},"exploited":true,"otx":{"pulseCount":50,"pulses":[{"name":"Actively_Exploited_Kev | Oct 29, 2026","url":"https://otx.alienvault.com/pulse/6ae20c1db17e7057ae7d9ad1","created":"2026-10-28"},{"name":"Actively_Exploited_Kev | Oct 28, 2026","url":"https://otx.alienvault.com/pulse/6ae0ba7e0e2a97ff7b218819","created":"2026-10-27"},{"name":"Actively_Exploited_Kev | Oct 27, 2026","url":"https://otx.alienvault.com/pulse/6adf68b85c3e852f3c111d18","created":"2026-10-26"},{"name":"Actively_Exploited_Kev | Oct 24, 2026","url":"https://otx.alienvault.com/pulse/6adb740e397c3ad4799aa4cd","created":"2026-10-23"},{"name":"Actively_Exploited_Kev | Oct 23, 2026","url":"https://otx.alienvault.com/pulse/6ada236fcfba2dfa730ea482","created":"2026-10-22"},{"name":"Actively_Exploited_Kev | Oct 22, 2026","url":"https://otx.alienvault.com/pulse/6ad8d33a077cbb5cab524d80","created":"2026-10-21"},{"name":"Actively_Exploited_Kev | Oct 21, 2026","url":"https://otx.alienvault.com/pulse/6ad78130c4d1ac2be83a8b6d","created":"2026-10-20"},{"name":"Actively_Exploited_Kev | Oct 20, 2026","url":"https://otx.alienvault.com/pulse/6ad62f63c24a405a3423cc13","created":"2026-10-19"},{"name":"Actively_Exploited_Kev | Oct 19, 2026","url":"https://otx.alienvault.com/pulse/6ad4dda174e5797d0bd238b7","created":"2026-10-18"},{"name":"Actively_Exploited_Kev | Oct 18, 2026","url":"https://otx.alienvault.com/pulse/6ad38c22e1848f8189d1c121","created":"2026-10-17"}],"provenance":"machine"},"cwes":[{"id":"CWE-416","name":"Use After Free"}],"references":[{"url":"http://seclists.org/fulldisclosure/2021/Sep/25","tags":["Mailing List","Third Party Advisory"]},{"url":"http://seclists.org/fulldisclosure/2021/Sep/27","tags":["Mailing List","Third Party Advisory"]},{"url":"http://seclists.org/fulldisclosure/2021/Sep/29","tags":["Mailing List","Third Party Advisory"]},{"url":"http://seclists.org/fulldisclosure/2021/Sep/38","tags":["Mailing List","Third Party Advisory"]},{"url":"http://seclists.org/fulldisclosure/2021/Sep/39","tags":["Mailing List","Third Party Advisory"]},{"url":"http://seclists.org/fulldisclosure/2021/Sep/50","tags":["Mailing List","Third Party Advisory"]},{"url":"http://www.openwall.com/lists/oss-security/2021/09/20/1","tags":["Mailing List"]},{"url":"http://www.openwall.com/lists/oss-security/2021/10/26/9","tags":["Mailing List"]},{"url":"http://www.openwall.com/lists/oss-security/2021/10/27/1","tags":["Mailing List"]},{"url":"http://www.openwall.com/lists/oss-security/2021/10/27/2","tags":["Mailing List"]},{"url":"http://www.openwall.com/lists/oss-security/2021/10/27/4","tags":["Mailing List"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BO6DMTHZR57JDBOXPSNR2MKDMCRWV265/","tags":["Release Notes"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XYNV7ASK4LQVAUMJXNXBS3Z7RVDQ2N3W/","tags":["Release Notes"]},{"url":"https://support.apple.com/en-us/HT212804","tags":["Third Party Advisory"]},{"url":"https://support.apple.com/en-us/HT212807","tags":["Third Party Advisory"]},{"url":"https://support.apple.com/kb/HT212824","tags":["Third Party Advisory"]},{"url":"https://www.debian.org/security/2021/dsa-4975","tags":["Mailing List","Third Party Advisory"]},{"url":"https://www.debian.org/security/2021/dsa-4976","tags":["Mailing List","Third Party Advisory"]},{"url":"http://seclists.org/fulldisclosure/2021/Sep/25","tags":["Mailing List","Third Party Advisory"]},{"url":"http://seclists.org/fulldisclosure/2021/Sep/27","tags":["Mailing List","Third Party Advisory"]},{"url":"http://seclists.org/fulldisclosure/2021/Sep/29","tags":["Mailing List","Third Party Advisory"]},{"url":"http://seclists.org/fulldisclosure/2021/Sep/38","tags":["Mailing List","Third Party Advisory"]},{"url":"http://seclists.org/fulldisclosure/2021/Sep/39","tags":["Mailing List","Third Party Advisory"]},{"url":"http://seclists.org/fulldisclosure/2021/Sep/50","tags":["Mailing List","Third Party Advisory"]},{"url":"http://www.openwall.com/lists/oss-security/2021/09/20/1","tags":["Mailing List"]},{"url":"http://www.openwall.com/lists/oss-security/2021/10/26/9","tags":["Mailing List"]},{"url":"http://www.openwall.com/lists/oss-security/2021/10/27/1","tags":["Mailing List"]},{"url":"http://www.openwall.com/lists/oss-security/2021/10/27/2","tags":["Mailing List"]},{"url":"http://www.openwall.com/lists/oss-security/2021/10/27/4","tags":["Mailing List"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BO6DMTHZR57JDBOXPSNR2MKDMCRWV265/","tags":["Release Notes"]},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XYNV7ASK4LQVAUMJXNXBS3Z7RVDQ2N3W/","tags":["Release Notes"]},{"url":"https://support.apple.com/en-us/HT212804","tags":["Third Party Advisory"]},{"url":"https://support.apple.com/en-us/HT212807","tags":["Third Party Advisory"]},{"url":"https://support.apple.com/kb/HT212824","tags":["Third Party Advisory"]},{"url":"https://www.debian.org/security/2021/dsa-4975","tags":["Mailing List","Third Party Advisory"]},{"url":"https://www.debian.org/security/2021/dsa-4976","tags":["Mailing List","Third Party Advisory"]},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-30858","tags":["US Government Resource"]}],"techniques":[{"id":"T1189","name":"Drive-by Compromise","tactics":["initial-access"],"provenance":"ai","basis":"ai-mapping","bases":["ai-mapping"],"basisDetail":"claude-haiku-5-5: malicious web content delivered to victim browser","mappingType":"exploitation_technique","evidence":[{"from":"description","quote":"Processing maliciously crafted web content","start":139,"end":181}],"model":"claude-haiku-5-5","confidence":"medium","confidenceNote":"AI-mapped from the description (quote-validated, not expert-reviewed)"},{"id":"T1059","name":"Command and Scripting 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expert-reviewed)"}],"reports":[],"affected":[],"advisories":[],"euvd":{"id":"EUVD-2021-17775","url":"https://euvd.enisa.europa.eu/vulnerability/EUVD-2021-17775","exploited":true,"exploitedSince":"2021-11-03","provenance":"source"},"exploits":[],"exploitSources":{"pocGithub":{"count":2,"skipped":0,"earliest":"2021-10-14","earliestUrl":"https://github.com/kmeps4/CVEREV3","repos":[{"name":"kmeps4/CVEREV3","url":"https://github.com/kmeps4/CVEREV3","stars":1,"created":"2021-10-14"},{"name":"Jeromeyoung/ps4_8.00_vuln_poc","url":"https://github.com/Jeromeyoung/ps4_8.00_vuln_poc","stars":0,"created":"2021-10-14"}]},"first":{"date":"2021-10-14","source":"PoC-in-GitHub","url":"https://github.com/kmeps4/CVEREV3"},"provenance":"source"},"exploitRefs":[],"flow":[{"stage":"exploitation","techniques":["T1189"],"provenance":"ai"},{"stage":"primary","techniques":["T1059"],"provenance":"ai"}],"timeline":[{"date":"2021-08-24","kind":"published","label":"Published 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KEV"},{"name":"Recent KEV listing","points":0.0,"detail":"added 1872 days ago"},{"name":"Known ransomware use","points":0.0,"detail":"not known"},{"name":"EPSS percentile","points":19.28,"detail":"percentile 0.9641"},{"name":"Named in threat reports","points":0.0,"detail":"0 reports"},{"name":"Public exploit code","points":5.0,"detail":"2 PoC-in-GitHub repos"},{"name":"Mentioned in OTX pulses","points":3.0,"detail":"50 pulses"},{"name":"CVSS severity","points":6.16,"detail":"base score 8.8"},{"name":"End-of-life product","points":0.0,"detail":"supported or unknown"}]},"lineage":{"familyId":"fam-class-apple-ios-macos-cwe-416"}}