{"cve":"CVE-2021-1883","nvd":{"published":"2021-09-08T15:15:12.513","modified":"2026-06-17T03:32:43.410","status":"Modified","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.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N","score":5.5},"cwes":["CWE-787"],"references":["https://support.apple.com/en-us/HT212317","https://support.apple.com/en-us/HT212323","https://support.apple.com/en-us/HT212324","https://support.apple.com/en-us/HT212325","https://support.apple.com/en-us/HT212530"],"products":["apple:ipados","apple:iphone_os","apple:mac_os_x","apple:macos","apple:tvos","apple:watchos"],"source":"nvd","synced_at":"2026-10-19T21:23:41.316049955+00:00"},"epss":{"cve":"CVE-2021-1883","score":0.01999,"percentile":0.8074,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}