CVE-2021-30858

8.8 HIGH CISA KEV - Actively Exploited
Published: August 24, 2021 Modified: October 27, 2025
View on NVD

Description

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.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
http://seclists.org/fulldisclosure/2021/Sep/25
Source: product-security@apple.com
Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2021/Sep/27
Source: product-security@apple.com
Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2021/Sep/29
Source: product-security@apple.com
Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2021/Sep/38
Source: product-security@apple.com
Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2021/Sep/39
Source: product-security@apple.com
Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2021/Sep/50
Source: product-security@apple.com
Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/09/20/1
Source: product-security@apple.com
Mailing List
http://www.openwall.com/lists/oss-security/2021/10/26/9
Source: product-security@apple.com
Mailing List
http://www.openwall.com/lists/oss-security/2021/10/27/1
Source: product-security@apple.com
Mailing List
http://www.openwall.com/lists/oss-security/2021/10/27/2
Source: product-security@apple.com
Mailing List
http://www.openwall.com/lists/oss-security/2021/10/27/4
Source: product-security@apple.com
Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BO6DMTHZR57JDBOXPSNR2MKDMCRWV265/
Source: product-security@apple.com
Release Notes
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XYNV7ASK4LQVAUMJXNXBS3Z7RVDQ2N3W/
Source: product-security@apple.com
Release Notes
https://support.apple.com/en-us/HT212804
Source: product-security@apple.com
Third Party Advisory
https://support.apple.com/en-us/HT212807
Source: product-security@apple.com
Third Party Advisory
https://support.apple.com/kb/HT212824
Source: product-security@apple.com
Third Party Advisory
https://www.debian.org/security/2021/dsa-4975
Source: product-security@apple.com
Mailing List Third Party Advisory
https://www.debian.org/security/2021/dsa-4976
Source: product-security@apple.com
Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2021/Sep/25
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2021/Sep/27
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2021/Sep/29
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2021/Sep/38
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2021/Sep/39
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2021/Sep/50
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/09/20/1
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List
http://www.openwall.com/lists/oss-security/2021/10/26/9
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List
http://www.openwall.com/lists/oss-security/2021/10/27/1
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List
http://www.openwall.com/lists/oss-security/2021/10/27/2
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List
http://www.openwall.com/lists/oss-security/2021/10/27/4
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BO6DMTHZR57JDBOXPSNR2MKDMCRWV265/
Source: af854a3a-2127-422b-91ae-364da2661108
Release Notes
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XYNV7ASK4LQVAUMJXNXBS3Z7RVDQ2N3W/
Source: af854a3a-2127-422b-91ae-364da2661108
Release Notes
https://support.apple.com/en-us/HT212804
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://support.apple.com/en-us/HT212807
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://support.apple.com/kb/HT212824
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://www.debian.org/security/2021/dsa-4975
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
https://www.debian.org/security/2021/dsa-4976
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-30858
Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
US Government Resource

37 reference(s) from NVD

Quick Stats

CVSS v3 Score
8.8 / 10.0
EPSS (Exploit Probability)
0.8%
73th percentile
Exploitation Status
Actively Exploited
Remediation due: 2021-11-17

Weaknesses (CWE)

CWE-416 CWE-416

Affected Vendors

debian fedoraproject apple

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