CVE-2021-30666

State: Published
Severity: 8.8 High
Published: Sep 8, 2021
Updated: Oct 21, 2025
Reserved: Apr 13, 2021

Description

A buffer overflow issue was addressed with improved memory handling. This issue is fixed in iOS 12.5.3. 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..

Scores

CVSS	Score	Vector	Source
3.1	8.8 High	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H	CISA-ADP

Weaknesses

CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer

Affected Products

Product	Versions
iOSApple	before 12.5Affected

References

https://support.apple.com/en-us/HT212341
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-30666government-resource

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