TI-2021-11051 Aliases CVE-2021-30666 GHSA-4cx8-frpf-fjc3

Memory corruption in Apple iOS

CRITICAL 97Exploited in the wildCWE-119Published 2021-09-08 · Updated 2025-10-21

Key facts

Attack vector: Network
Privileges required: None
User interaction: Required
Attack complexity: Low
Impact type: Code execution
Confidentiality · integrity · availability: High · High · High
Fix status: Partial Red Hat: 11 fixed, 2 without a fix

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-119 and the CVSS impact.

Summary

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..

Why it matters now

Exploitation Active In CISA KEV since 2021-11-03CISA due date 2021-11-17

EPSS 0.02998 87th percentileScored 2026-11-07

Fix Partial iOS (Apple): 12.5Red Hat: 3 advisoriesRed Hat: 11 fixed, 2 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Active
Automatable: No
Technical impact: Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Apple	iOS	before 12.5	12.5	Patch available	CNA

iOS VendorApple Affected before 12.5 Fixed in 12.5 Patch available CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:o:apple:iphone_os::::::::	before 12.5.3	Vulnerable	Apple

cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:* Versions before 12.5.3 Vulnerable ·Apple

Remediation

Fix · CNA iOS (Apple) Fixed in 12.5

Red Hat 3 advisories

RHSA-2025:10364 Released 2025-07-07 · Red Hat rating Important
webkitgtk4 security update
- Red Hat Enterprise Linux Server (v. 7 ELS) webkitgtk4-2.48.3-2.el7_9, webkitgtk4-devel-2.48.3-2.el7_9, webkitgtk4-jsc-2.48.3-2.el7_9 +1
- Red Hat Enterprise Linux Server Optional (v. 7 ELS) webkitgtk4-devel-2.48.3-2.el7_9, webkitgtk4-doc-2.48.3-2.el7_9, webkitgtk4-jsc-devel-2.48.3-2.el7_9
RHSA-2020:4451 Released 2020-11-04 · Red Hat rating Moderate
GNOME security, bug fix, and enhancement update
- Red Hat CodeReady Linux Builder (v. 8) LibRaw-devel-0.19.5-2.el8
- Red Hat Enterprise Linux AppStream (v. 8) LibRaw-0.19.5-2.el8, gnome-settings-daemon-3.32.0-11.el8, webkit2gtk3-2.28.4-1.el8 +3
RHSA-2020:4035 Released 2020-09-29 · Red Hat rating Moderate
webkitgtk4 security, bug fix, and enhancement update
- Red Hat Enterprise Linux Client (v. 7) webkitgtk4-2.28.2-2.el7, webkitgtk4-jsc-2.28.2-2.el7
- Red Hat Enterprise Linux Client Optional (v. 7) webkitgtk4-devel-2.28.2-2.el7, webkitgtk4-doc-2.28.2-2.el7, webkitgtk4-jsc-devel-2.28.2-2.el7
- Red Hat Enterprise Linux ComputeNode (v. 7) webkitgtk4-2.28.2-2.el7, webkitgtk4-jsc-2.28.2-2.el7
- Red Hat Enterprise Linux ComputeNode Optional (v. 7) webkitgtk4-devel-2.28.2-2.el7, webkitgtk4-doc-2.28.2-2.el7, webkitgtk4-jsc-devel-2.28.2-2.el7
- Red Hat Enterprise Linux Server (v. 7) webkitgtk4-2.28.2-2.el7, webkitgtk4-2.28.2-2.el7.ppc, webkitgtk4-devel-2.28.2-2.el7 +3
- Red Hat Enterprise Linux Server Optional (v. 7) webkitgtk4-devel-2.28.2-2.el7, webkitgtk4-devel-2.28.2-2.el7.ppc, webkitgtk4-doc-2.28.2-2.el7 +2
- Red Hat Enterprise Linux Workstation (v. 7) webkitgtk4-2.28.2-2.el7, webkitgtk4-devel-2.28.2-2.el7, webkitgtk4-jsc-2.28.2-2.el7 +1
- Red Hat Enterprise Linux Workstation Optional (v. 7) webkitgtk4-doc-2.28.2-2.el7

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

Release · 2021-09-08
Apple iOS 12.5
3 records Highest priority Priority CRITICAL 3 CRITICAL
Other records, highest priority first
- TI-2021-11140 Use after free in Apple iOSPriority CRITICAL 97
- TI-2021-11139 Out-of-bounds write in Apple iOSPriority CRITICAL 97
Show all 3 records →

Vendor assessments

Red Hat

Red Hat rating: Moderate. Red Hat's page for this CVE →

Product	Status	Plan or fix
Red Hat Enterprise Linux 6	Affected	No fix yet
Red Hat Enterprise Linux 7	Affected	No fix yet
Red Hat Enterprise Linux AppStream (v. 8)	Fixed	RHSA-2020:4451
Red Hat Enterprise Linux Client (v. 7)	Fixed	RHSA-2020:4035
Red Hat Enterprise Linux Client Optional (v. 7)	Fixed	RHSA-2020:4035
Red Hat Enterprise Linux ComputeNode (v. 7)	Fixed	RHSA-2020:4035
Red Hat Enterprise Linux ComputeNode Optional (v. 7)	Fixed	RHSA-2020:4035
Red Hat Enterprise Linux Server (v. 7 ELS)	Fixed	RHSA-2025:10364
Red Hat Enterprise Linux Server (v. 7)	Fixed	RHSA-2020:4035
Red Hat Enterprise Linux Server Optional (v. 7 ELS)	Fixed	RHSA-2025:10364
Red Hat Enterprise Linux Server Optional (v. 7)	Fixed	RHSA-2020:4035
Red Hat Enterprise Linux Workstation (v. 7)	Fixed	RHSA-2020:4035
Red Hat Enterprise Linux Workstation Optional (v. 7)	Fixed	RHSA-2020:4035

Not affected: 4 products

Red Hat CodeReady Linux Builder (v. 8)
Red Hat Enterprise Linux 9
Red Hat Enterprise Linux AppStream (v. 8)
Red Hat Enterprise Linux BaseOS (v. 8)

Timeline

2021-11-03 Added to CISA KEV
2026-10-02 Threatist record created from CVE-2021-30666
2026-10-03 Alias added: GHSA-4cx8-frpf-fjc3

References

Advisory 2

TI-2025-28008 Out-of-bounds write in Apple iOS and iPadOS KEVCVSS 3.1CRITICAL 10.0
TI-2025-22441 Apple iOS and iPadOS: An attacker with arbitrary read and write capability may be able to… KEVCVSS 3.1CRITICAL 9.8
TI-2025-22440 Memory corruption in Apple iOS and iPadOS KEVCVSS 3.1CRITICAL 9.8
TI-2025-17951 Out-of-bounds write in Apple Safari KEVCVSS 3.1CRITICAL 10.0
TI-2025-17847 Use after free in Apple iOS and iPadOS KEVCVSS 3.1CRITICAL 10.0
TI-2022-06854 Out-of-bounds write in Apple iOS and iPadOS KEVCVSS 3.1CRITICAL 9.8

See all 4500 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences