VDB-362874 · CVE-2026-43666 · GCVE-0-2026-43666

Apple iOS/iPadOS/macOS/tvOS/visionOS/watchOS up to 18.7.8/26.4 out-of-bounds write

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.
6.2	$5k-$25k	0.00

Summaryinfo

A vulnerability categorized as critical has been discovered in Apple iOS, iPadOS, macOS, tvOS, visionOS and watchOS up to 18.7.8/26.4. The affected element is an unknown function. The manipulation results in out-of-bounds write. This vulnerability is cataloged as CVE-2026-43666. The attack must originate from the local network. There is no exploit available. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Apple iOS, iPadOS, macOS, tvOS, visionOS and watchOS up to 18.7.8/26.4. Affected is an unknown functionality. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. CWE is classifying the issue as CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. This is going to have an impact on availability. CVE summarizes:

An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 18.7.9 and iPadOS 18.7.9, iOS 26.5 and iPadOS 26.5, macOS Sequoia 15.7.7, macOS Sonoma 14.8.7, macOS Tahoe 26.5, tvOS 26.5, visionOS 26.5, watchOS 26.5. An attacker on the local network may be able to cause a denial-of-service.

The advisory is available at support.apple.com. This vulnerability is traded as CVE-2026-43666 since 05/02/2026. The exploitability is told to be easy. The attack can only be done within the local network. The exploitation doesn't require any form of authentication. The technical details are unknown and an exploit is not available. The structure of the vulnerability defines a possible price range of USD $5k-$25k at the moment (estimation calculated on 05/12/2026).

Upgrading to version 18.7.9 or 26.5 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit 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: 6.5
VulDB Meta Temp Score: 6.2

VulDB Base Score: 6.5
VulDB Temp Score: 6.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
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: 🔍

0-Day Time: 🔒

Upgrade: iOS/iPadOS/macOS/tvOS/visionOS/watchOS 18.7.9/26.5

Timelineinfo

05/02/2026 CVE reserved
05/12/2026 +10 days Advisory disclosed
05/12/2026 +0 days VulDB entry created
05/12/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: apple.com

Advisory: support.apple.com
Status: Confirmed

CVE: CVE-2026-43666 (🔒)
GCVE (CVE): GCVE-0-2026-43666
GCVE (VulDB): GCVE-100-362874
scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 05/12/2026 04:25
Changes: 05/12/2026 04:25 (56)
Complete: 🔍
Cache ID: 216::103