Apple iOS up to 12.5.4 XNU Kernel type confusion

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
7.7	$5k-$25k	0.00

Summaryinfo

A vulnerability has been found in Apple iOS up to 12.5.4 and classified as critical. The impacted element is an unknown function of the component XNU Kernel. Performing a manipulation results in type confusion. This vulnerability was named CVE-2021-30869. The attack needs to be approached locally. In addition, an exploit is available. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as critical, was found in Apple iOS up to 12.5.4 (Smartphone Operating System). This affects an unknown part of the component XNU Kernel. The manipulation with an unknown input leads to a type confusion vulnerability. CWE is classifying the issue as CWE-843. The product allocates or initializes a resource such as a pointer, object, or variable using one type, but it later accesses that resource using a type that is incompatible with the original type. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

A type confusion issue was addressed with improved state handling. This issue is fixed in iOS 12.5.5, iOS 14.4 and iPadOS 14.4, macOS Big Sur 11.2, Security Update 2021-001 Catalina, Security Update 2021-001 Mojave, Security Update 2021-006 Catalina. A malicious application may be able to execute arbitrary code with kernel privileges. Apple is aware of reports that an exploit for this issue exists in the wild.

The weakness was presented 09/24/2021 as HT212824. The advisory is shared at support.apple.com. This vulnerability is uniquely identified as CVE-2021-30869. Technical details are unknown but an exploit is available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 07/29/2025). It is expected to see the exploit prices for this product increasing in the near future.

It is declared as attacked. The CISA Known Exploited Vulnerabilities Catalog lists this issue since 11/03/2021 with a due date of 11/17/2021:

Apply updates per vendor instructions.

Upgrading to version 12.5.5 eliminates this vulnerability.

The vulnerability is also documented in the databases at Zero-Day.cz (665) and EUVD (EUVD-2021-17786). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

Smartphone Operating System

Vendor

Apple

Name

Version

License

commercial

Website

Vendor: https://www.apple.com/

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.8
VulDB Meta Temp Score: 7.7

VulDB Base Score: 7.8
VulDB Temp Score: 7.5
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CNA Base Score: 7.8
CNA Vector: 🔍

CVSSv2info

AV	AC	Au	C	I	A
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Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Type confusion
CWE: CWE-843
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Status: Attacked

EPSS Score: 🔍
EPSS Percentile: 🔍

KEV Added: 🔍
KEV Due: 🔍
KEV Remediation: 🔍
KEV Ransomware: 🔍
KEV Notice: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

0-Day	Unlock	Unlock	Unlock	Unlock
Today	Unlock	Unlock	Unlock	Unlock

Zero-Day.cz: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Upgrade: iOS 12.5.5

Timelineinfo

04/13/2021 🔍
09/24/2021 +164 days 🔍
09/24/2021 +0 days 🔍
07/29/2025 +1404 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT212824
Status: Confirmed

CVE: CVE-2021-30869 (🔍)
GCVE (CVE): GCVE-0-2021-30869
GCVE (VulDB): GCVE-100-183333
EUVD: 🔍
scip Labs: https://www.scip.ch/en/?labs.20150917

Entryinfo

Created: 09/24/2021 19:50
Updated: 07/29/2025 04:48
Changes: 09/24/2021 19:50 (42), 10/02/2021 10:05 (1), 04/21/2024 18:40 (23), 06/24/2024 20:27 (2), 07/29/2024 23:25 (19), 09/15/2024 00:30 (1), 01/30/2025 00:15 (10), 07/29/2025 04:48 (1)
Complete: 🔍
Cache ID: 216::103

If you want to get the best quality for vulnerability data then you always have to consider VulDB.