CVE-2021-30858

Known Exploited

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.

Category

8.8
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 1.03% Top 25%
KEV Since 
Vendor Advisory fedoraproject.org Vendor Advisory debian.org Vendor Advisory debian.org Vendor Advisory fedoraproject.org
Affected: Apple macOS
Affected: Apple iOS
Published at:
Updated at:

References

Link Tags
https://support.apple.com/en-us/HT212804 third party advisory
https://support.apple.com/en-us/HT212807 third party advisory
http://seclists.org/fulldisclosure/2021/Sep/27 third party advisory mailing list
http://seclists.org/fulldisclosure/2021/Sep/25 third party advisory mailing list
http://seclists.org/fulldisclosure/2021/Sep/29 third party advisory mailing list
http://www.openwall.com/lists/oss-security/2021/09/20/1 mailing list
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BO6DMTHZR57JDBOXPSNR2MKDMCRWV265/ release notes vendor advisory
http://seclists.org/fulldisclosure/2021/Sep/38 third party advisory mailing list
http://seclists.org/fulldisclosure/2021/Sep/39 third party advisory mailing list
https://www.debian.org/security/2021/dsa-4975 vendor advisory mailing list third party advisory
https://www.debian.org/security/2021/dsa-4976 vendor advisory mailing list third party advisory
https://support.apple.com/kb/HT212824 third party advisory
http://seclists.org/fulldisclosure/2021/Sep/50 third party advisory mailing list
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/XYNV7ASK4LQVAUMJXNXBS3Z7RVDQ2N3W/ release notes vendor advisory
http://www.openwall.com/lists/oss-security/2021/10/26/9 mailing list
http://www.openwall.com/lists/oss-security/2021/10/27/1 mailing list
http://www.openwall.com/lists/oss-security/2021/10/27/2 mailing list
http://www.openwall.com/lists/oss-security/2021/10/27/4 mailing list

Frequently Asked Questions

What is the severity of CVE-2021-30858?
CVE-2021-30858 has been scored as a high severity vulnerability.
How to fix CVE-2021-30858?
To fix CVE-2021-30858, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-30858 being actively exploited in the wild?
It is confirmed that CVE-2021-30858 is actively exploited. Be extra cautious if you are using vulnerable components. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-30858?
CVE-2021-30858 affects Apple macOS, Apple iOS.
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