{"id":"CVE-2021-1883","url":"https://www.cyber-defence.io/tools/cve/CVE-2021-1883","generatedAt":"2026-10-27T21:19:06.596Z","title":"Processing maliciously crafted server messages may lead to heap corruption.","description":"This issue was addressed with improved checks. This issue is fixed in Security Update 2021-004 Mojave, iOS 14.5 and iPadOS 14.5, watchOS 7.4, Security Update 2021-003 Catalina, tvOS 14.5, macOS Big Sur 11.3. Processing maliciously crafted server messages may lead to heap corruption.","published":"2021-09-08T15:15:13.000Z","lastModified":"2026-06-17T03:32:43.000Z","status":"Modified","sourceIdentifier":"product-security@apple.com","cvss":{"version":"3.1","score":5.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N"},"cwe":["CWE-787"],"affected":["apple/ipados","apple/iphone os","apple/mac os x","apple/macos","apple/tvos","apple/watchos"],"epss":{"score":0.01999,"percentile":0.80602,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (2.00%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://support.apple.com/en-us/HT212317","tags":["Vendor Advisory"],"source":"product-security@apple.com"},{"url":"https://support.apple.com/en-us/HT212323","tags":["Vendor Advisory"],"source":"product-security@apple.com"},{"url":"https://support.apple.com/en-us/HT212324","tags":["Vendor Advisory"],"source":"product-security@apple.com"},{"url":"https://support.apple.com/en-us/HT212325","tags":["Vendor Advisory"],"source":"product-security@apple.com"},{"url":"https://support.apple.com/en-us/HT212530","tags":["Vendor Advisory"],"source":"product-security@apple.com"},{"url":"https://support.apple.com/en-us/HT212531","tags":["Vendor Advisory"],"source":"product-security@apple.com"},{"url":"https://support.apple.com/en-us/HT212317","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://support.apple.com/en-us/HT212323","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://support.apple.com/en-us/HT212324","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://support.apple.com/en-us/HT212325","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://support.apple.com/en-us/HT212530","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://support.apple.com/en-us/HT212531","tags":["Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2021-1883","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."}