{"id":"CVE-2021-1870","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-1870","generatedAt":"2026-10-27T21:19:42.938Z","title":"Apple iOS, iPadOS, and macOS WebKit Remote Code Execution Vulnerability","description":"A logic issue was addressed with improved restrictions. This issue is fixed in macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, iOS 14.4 and iPadOS 14.4. A remote attacker may be able to cause arbitrary code execution. Apple is aware of a report that this issue may have been actively exploited..","published":"2021-04-02T19:15:21.000Z","lastModified":"2026-06-17T03:32:42.000Z","status":"Analyzed","sourceIdentifier":"product-security@apple.com","cvss":{"version":"3.1","score":9.8,"severity":"CRITICAL","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"},"cwe":[],"affected":["apple/ipados","apple/iphone os","apple/mac os x","apple/macos","webkitgtk/webkitgtk","fedoraproject/fedora"],"epss":{"score":0.0771,"percentile":0.94572,"date":"2026-10-26","history":[]},"kev":{"listed":true,"dateAdded":"2021-11-03","dueDate":"2021-11-17","knownRansomwareCampaignUse":"Unknown","notes":"Apply updates per vendor instructions.\nhttps://nvd.nist.gov/vuln/detail/CVE-2021-1870"},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"urgent","text":"Known to be exploited in the wild (CISA KEV, CISA remediation deadline 17 November 2021). Treat as an emergency change: patch or isolate now, then hunt for prior compromise."},"changes":[],"references":[{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JN6ZOD62CTO54CHTMJTHVEF6R2Y532TJ/","tags":["Broken Link","Mailing List"],"source":"product-security@apple.com"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L3L6ZZOU5JS7E3RFYGLP7UFLXCG7TNLU/","tags":["Broken Link","Mailing List"],"source":"product-security@apple.com"},{"url":"https://security.gentoo.org/glsa/202104-03","tags":["Third Party Advisory"],"source":"product-security@apple.com"},{"url":"https://support.apple.com/en-us/HT212146","tags":["Release Notes","Vendor Advisory"],"source":"product-security@apple.com"},{"url":"https://support.apple.com/en-us/HT212147","tags":["Release Notes","Vendor Advisory"],"source":"product-security@apple.com"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/JN6ZOD62CTO54CHTMJTHVEF6R2Y532TJ/","tags":["Broken Link","Mailing List"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/L3L6ZZOU5JS7E3RFYGLP7UFLXCG7TNLU/","tags":["Broken Link","Mailing List"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://security.gentoo.org/glsa/202104-03","tags":["Third Party Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://support.apple.com/en-us/HT212146","tags":["Release Notes","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://support.apple.com/en-us/HT212147","tags":["Release Notes","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-1870","tags":["US Government Resource"],"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-1870","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}