8.8High KEV

CVE-2021-30858Apple iOS, iPadOS, macOS Use-After-Free Vulnerability

Apple macOS; Apple iOS Published: 2021-08-24 21:49 (5 years ago)

Known exploited — Apple iOS, iPadOS, macOS Use-After-Free Vulnerability

CISA confirmed this vulnerability is used in real attacks on 03.11.2021. Remediation deadline for US federal agencies: 17.11.2021.

Required action: Apply updates per vendor instructions. https://nvd.nist.gov/vuln/detail/CVE-2021-30858

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.

Weakness (CWE): CWE-416

Data: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Published as the sources state it, in English.

Affected products and versions

Vendor	Product	Versions
Apple	iOS	unspecified – < 14.8
apple	ipados	13.1 – < 14.8
apple	iphone os	< 12.5.5
Apple	macOS	unspecified – < 11.6
debian	debian linux	10.0
fedoraproject	fedora	33

References and patches

https://support.apple.com/en-us/HT212804 Third Party Advisory
https://support.apple.com/en-us/HT212807 Third Party Advisory
20210917 APPLE-SA-2021-09-13-3 macOS Big Sur 11.6 mailing-listMailing ListThird Party Advisory
20210917 APPLE-SA-2021-09-13-1 iOS 14.8 and iPadOS 14.8 mailing-listMailing ListThird Party Advisory
20210917 APPLE-SA-2021-09-13-5 Safari 14.1.2 mailing-listMailing ListThird Party Advisory
[oss-security] 20210920 WebKitGTK and WPE WebKit Security Advisory WSA-2021-0005 mailing-listMailing List
FEDORA-2021-c00e45b6c0 vendor-advisoryRelease Notes
20210921 APPLE-SA-2021-09-20-6 Additional information for APPLE-SA-2021-09-13-1 iOS 14.8 and iPadOS 14.8 mailing-listMailing ListThird Party Advisory
20210921 APPLE-SA-2021-09-20-7 Additional information for APPLE-SA-2021-09-13-3 macOS Big Sur 11.6 mailing-listMailing ListThird Party Advisory
DSA-4975 vendor-advisoryMailing ListThird Party Advisory
DSA-4976 vendor-advisoryMailing ListThird Party Advisory
https://support.apple.com/kb/HT212824 Third Party Advisory
20210924 APPLE-SA-2021-09-23-1 iOS 12.5.5 mailing-listMailing ListThird Party Advisory
FEDORA-2021-edf6957b7d vendor-advisoryRelease Notes
[oss-security] 20211026 WebKitGTK and WPE WebKit Security Advisory WSA-2021-0006 mailing-listMailing List
[oss-security] 20211027 Re: WebKitGTK and WPE WebKit Security Advisory WSA-2021-0006 mailing-listMailing List
[oss-security] 20211027 Re: WebKitGTK and WPE WebKit Security Advisory WSA-2021-0006 mailing-listMailing List
[oss-security] 20211027 Re: WebKitGTK and WPE WebKit Security Advisory WSA-2021-0006 mailing-listMailing List
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-30858 US Government Resource

CPE matches (NVD) (8)

cpe:2.3:o:apple:ipados:*:*:*:*:*:*:*:* ≥ 13.1 < 14.8
cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:* < 12.5.5
cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:* ≥ 13.0 < 14.8
cpe:2.3:o:apple:macos:*:*:*:*:*:*:*:* < 11.6
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*
cpe:2.3:o:fedoraproject:fedora:34:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:11.0:*:*:*:*:*:*:*

CVSS score

8.8High

Source: CISA-ADP · CVSS 3.1

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: Required
Scope: Unchanged
Confidentiality: High
Integrity: High
Availability: High

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

All scores (4)

CISA-ADP	CVSS 3.1	8.8High
nvd	CVSS 3.1	8.8High
134c704f-9b21-4f2e-91b3-4a467353bcc0	CVSS 3.1	8.8High
nvd	CVSS 2.0	6.8Medium

EPSS (chance of exploitation in 30 days)

13.38%

higher than 96% of all CVEs

CISA assessment (SSVC)

Exploitation: active
Automatable: no
Technical impact: total

Timeline

ID reserved2021-04-13
Published2021-08-24 21:49
Reached IP-DB2026-10-24 23:34
Added to KEV2021-11-03
Last updated2026-06-17 06:51

Assigned by (CNA): apple
NVD status: Analyzed

View at source: CVE.org · NVD

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