Apple iOS/iPadOS up to 16.3.1 Apple Neural Engine memory corruption

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.
7.6	$5k-$25k	0.00

Summaryinfo

A vulnerability was found in Apple iOS and iPadOS up to 16.3.1. It has been rated as critical. The affected element is an unknown function of the component Apple Neural Engine. This manipulation causes memory corruption. The identification of this vulnerability is CVE-2023-27959. The attack can only be executed locally. There is no exploit available. Upgrading the affected component is advised.

Detailsinfo

A vulnerability has been found in Apple iOS and iPadOS up to 16.3.1 (Smartphone Operating System) and classified as critical. Affected by this vulnerability is an unknown function of the component Apple Neural Engine. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

The issue was addressed with improved memory handling. This issue is fixed in iOS 16.4 and iPadOS 16.4. An app may be able to execute arbitrary code with kernel privileges.

The weakness was shared 03/27/2023 by Mohamed Ghannam as HT213676 as confirmed advisory (Website). The advisory is shared at support.apple.com. This vulnerability is known as CVE-2023-27959. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 11/30/2025). It is expected to see the exploit prices for this product increasing in the near future. The advisory points out:

An app may be able to execute arbitrary code with kernel privileges

Upgrading to version 16.4 eliminates this vulnerability. A possible mitigation has been published immediately after the disclosure of the vulnerability. The advisory contains the following remark:

The issue was addressed with improved memory handling.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2023-31685). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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: 7.6

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

NVD Base Score: 7.8
NVD Vector: 🔍

CVSSv2info

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

Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Upgrade: iOS/iPadOS 16.4

Timelineinfo

03/08/2023 🔍
03/27/2023 +18 days 🔍
03/27/2023 +0 days 🔍
03/29/2023 +2 days 🔍
11/30/2025 +977 days 🔍

Sourcesinfo

Vendor: apple.com

Advisory: HT213676
Researcher: Mohamed Ghannam
Status: Confirmed

CVE: CVE-2023-27959 (🔍)
GCVE (CVE): GCVE-0-2023-27959
GCVE (VulDB): GCVE-100-224329
EUVD: 🔍
scip Labs: https://www.scip.ch/en/?labs.20150917

Entryinfo

Created: 03/29/2023 09:46
Updated: 11/30/2025 05:05
Changes: 03/29/2023 09:46 (18), 03/29/2023 09:47 (1), 03/29/2023 09:50 (28), 04/16/2023 17:40 (1), 12/12/2024 16:40 (26), 11/30/2025 05:05 (1)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.