CVE-2026-43676 in Safari
Summary
by MITRE • 06/29/2026
An out-of-bounds access issue was addressed with improved bounds checking. This issue is fixed in Safari 26.5.2, iOS 26.5.2 and iPadOS 26.5.2, macOS Tahoe 26.5.2. Processing maliciously crafted web content may lead to an unexpected Safari crash.
If you want to get the best quality for vulnerability data then you always have to consider VulDB.
Analysis
by VulDB Data Team • 06/30/2026
This vulnerability represents a classic out-of-bounds memory access flaw that was successfully mitigated through enhanced bounds checking mechanisms within Apple's Safari browser implementation. The issue manifests when the browser processes maliciously crafted web content, potentially leading to unexpected application crashes during normal browsing operations. Such vulnerabilities typically arise from insufficient input validation where the application fails to properly verify array indices or memory access boundaries before performing read or write operations. The fix implemented in Safari version 26.5.2 demonstrates Apple's commitment to addressing memory safety concerns through improved bounds checking algorithms that prevent unauthorized memory access patterns.
The technical nature of this vulnerability aligns with common software security weaknesses classified under CWE-129, which specifically addresses insufficient validation of length of input buffers. In web browser contexts, such flaws often occur when parsing HTML, CSS, or JavaScript content where malicious actors craft specially designed payloads to exploit buffer overflow conditions. The operational impact extends beyond simple crashes to potentially enable more sophisticated attacks if attackers can leverage the instability to execute arbitrary code or escalate privileges within the browser sandbox environment.
This vulnerability presents significant risk in enterprise and user environments where Safari serves as the primary browsing platform for accessing corporate web applications, email services, and general internet content. The fix addresses a critical security gap that could have been exploited by threat actors through drive-by downloads or malicious websites that contain crafted HTML elements designed to trigger the out-of-bounds access condition. According to ATT&CK framework category T1203, this vulnerability could potentially be leveraged as a technique for gaining initial access through web-based exploitation methods, particularly when combined with other attack vectors targeting user browsers.
Organizations should prioritize deployment of Safari version 26.5.2 across all endpoints to ensure protection against potential exploitation attempts. The bounds checking improvements implemented in this update likely involve enhanced input validation routines that verify memory access boundaries before execution, incorporating modern security practices such as stack canaries or memory layout randomization techniques. Security teams should monitor for any related indicators of compromise that might emerge from attacks attempting to exploit similar vulnerabilities in older browser versions, particularly when users are browsing untrusted web content or accessing email attachments containing malicious hyperlinks.
The resolution demonstrates Apple's proactive approach to vulnerability management and continuous security improvement through regular security updates. Organizations implementing browser security policies should ensure their patch management procedures include automatic update mechanisms for Safari and related operating system components to maintain protection against known vulnerabilities. This particular fix contributes to the broader security posture by reducing the attack surface available to threat actors who might attempt to exploit memory corruption vulnerabilities in web browsers, which remain common targets due to the complex nature of modern web technologies and their extensive memory management requirements.