Apple iOS/iPadOS/macOS/tvOS/visionOS/watchOS prior 26.6/15.7.8/14.8.8 out-of-bounds write

CVSS Meta Temp Score
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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.
9.5$25k-$100k1.41

Summaryinfo

A vulnerability marked as very critical has been reported in Apple iOS, iPadOS, macOS, tvOS, visionOS and watchOS. Affected by this vulnerability is an unknown functionality. Performing a manipulation results in out-of-bounds write. This vulnerability is known as CVE-2026-43803. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability classified as very critical has been found in Apple iOS, iPadOS, macOS, tvOS, visionOS and watchOS. This affects an unknown code. 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 confidentiality, integrity, and availability. The summary by CVE is:

An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 26.6 and iPadOS 26.6, macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6, tvOS 26.6, visionOS 26.6, watchOS 26.6. A remote attacker may be able to cause unexpected system termination.

The advisory is shared at support.apple.com. This vulnerability is uniquely identified as CVE-2026-43803 since 05/02/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $25k-$100k at the moment (estimation calculated on 07/27/2026).

Upgrading to version 26.6, 15.7.8 or 14.8.8 eliminates this vulnerability.

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

Productinfo

Type

Vendor

Name

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 9.9
VulDB Meta Temp Score: 9.5

VulDB Base Score: 9.9
VulDB Temp Score: 9.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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💳💳💳💳💳💳
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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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: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: iOS/iPadOS/macOS/tvOS/visionOS/watchOS 26.6/15.7.8/14.8.8

Timelineinfo

05/02/2026 CVE reserved
07/27/2026 +86 days Advisory disclosed
07/27/2026 +0 days VulDB entry created
07/27/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: apple.com

Advisory: support.apple.com
Status: Confirmed

CVE: CVE-2026-43803 (🔒)
GCVE (CVE): GCVE-0-2026-43803
GCVE (VulDB): GCVE-100-383625
scip Labs: https://www.scip.ch/en/?labs.20180712

Entryinfo

Created: 07/27/2026 23:45
Changes: 07/27/2026 23:45 (54)
Complete: 🔍
Cache ID: 216::103

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

Discussion

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