An out-of-bounds write issue was addressed with improved bounds checking. (CVE-2026-43803)
CVE-2026-43803 is a critical out-of-bounds write vulnerability affecting multiple Apple operating systems. The issue was addressed by improved bounds checking and fixed in iOS 26.6, iPadOS 26.6, macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6, tvOS 26.6, visionOS 26.6, and watchOS 26.6. A remote attacker could exploit this flaw to cause unexpected system termination, impacting confidentiality, integrity, and availability.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-43803) involves an out-of-bounds write due to insufficient bounds checking in Apple operating systems. The flaw allows a remote attacker to cause unexpected system termination, which affects system stability and security. The issue is classified under CWE-787. It has a CVSS 3.1 base score of 9.8, indicating critical severity with network attack vector, low attack complexity, no privileges or user interaction required, and high impact on confidentiality, integrity, and availability. The vendor fixed this issue in iOS 26.6, iPadOS 26.6, macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6, tvOS 26.6, visionOS 26.6, and watchOS 26.6.
Potential Impact
A remote attacker can exploit this vulnerability to cause unexpected system termination, potentially leading to denial of service and compromising system confidentiality, integrity, and availability.
Mitigation Recommendations
This vulnerability has been fixed by Apple in iOS 26.6, iPadOS 26.6, macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6, tvOS 26.6, visionOS 26.6, and watchOS 26.6. Users and administrators should apply these official updates to remediate the issue.
An out-of-bounds write issue was addressed with improved bounds checking. (CVE-2026-43803)
Description
CVE-2026-43803 is a critical out-of-bounds write vulnerability affecting multiple Apple operating systems. The issue was addressed by improved bounds checking and fixed in iOS 26.6, iPadOS 26.6, macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6, tvOS 26.6, visionOS 26.6, and watchOS 26.6. A remote attacker could exploit this flaw to cause unexpected system termination, impacting confidentiality, integrity, and availability.
CVSS v3.1
Score 9.8critical
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-43803) involves an out-of-bounds write due to insufficient bounds checking in Apple operating systems. The flaw allows a remote attacker to cause unexpected system termination, which affects system stability and security. The issue is classified under CWE-787. It has a CVSS 3.1 base score of 9.8, indicating critical severity with network attack vector, low attack complexity, no privileges or user interaction required, and high impact on confidentiality, integrity, and availability. The vendor fixed this issue in iOS 26.6, iPadOS 26.6, macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6, tvOS 26.6, visionOS 26.6, and watchOS 26.6.
Potential Impact
A remote attacker can exploit this vulnerability to cause unexpected system termination, potentially leading to denial of service and compromising system confidentiality, integrity, and availability.
Mitigation Recommendations
This vulnerability has been fixed by Apple in iOS 26.6, iPadOS 26.6, macOS Sequoia 15.7.8, macOS Sonoma 14.8.8, macOS Tahoe 26.6, tvOS 26.6, visionOS 26.6, and watchOS 26.6. Users and administrators should apply these official updates to remediate the issue.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- GHSA-mv2g-98jj-rj6f
- Osv Schema Version
- 1.4.0
- Aliases
- ["CVE-2026-43803"]
- Ecosystems
- []
- Database Specific Severity
- CRITICAL
- Cvss Version
- 3.1
Threat ID: 6a83aa79bf8831d539e3248c
Added to database: 08/18/2026, 00:42:33 UTC
Last enriched: 08/18/2026, 00:58:38 UTC
Last updated: 08/18/2026, 01:52:59 UTC
Views: 3
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