CVE-2026-64783 in Safari
Summary
by MITRE • 07/28/2026
A use-after-free issue was addressed with improved memory management. This issue is fixed in Safari 26.6, iOS 26.6 and iPadOS 26.6, macOS Tahoe 26.6, visionOS 26.6, watchOS 26.6. Processing maliciously crafted web content may lead to an unexpected Safari crash.
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Analysis
by VulDB Data Team • 07/28/2026
This vulnerability represents a classic use-after-free condition that was remediated through enhanced memory management mechanisms within Apple's web browser ecosystem. The flaw occurred when Safari processed maliciously crafted web content that triggered improper memory deallocation followed by subsequent access to freed memory regions. Such conditions create exploitable vectors where attackers can manipulate memory state to execute arbitrary code or cause application instability. The vulnerability affects multiple Apple platforms including iOS, iPadOS, macOS, visionOS, and watchOS, indicating a widespread impact across the company's ecosystem. According to CWE-416, this represents a specific instance of improper cleanup after use, where memory resources are freed but references to them persist in the application's execution flow.
The technical exploitation of this vulnerability requires careful crafting of web content that can trigger the specific memory management race condition within Safari's rendering engine. When malicious content is processed, the browser's memory allocator may prematurely release memory blocks that are still referenced by active code paths, creating a window where attackers can overwrite freed memory with controlled data. This type of vulnerability typically falls under the ATT&CK framework's technique T1203 for legitimate program execution and T1059 for command and scripting interpreter usage. The impact manifests as unexpected application crashes during content rendering, though the underlying memory corruption could potentially enable more sophisticated exploitation techniques if not properly addressed.
The remediation implemented in Safari 26.6 and associated platform versions demonstrates Apple's approach to addressing memory safety issues through improved garbage collection mechanisms and enhanced memory validation routines. These updates likely incorporate additional checks for pointer validity before memory access operations, implement stricter memory allocation patterns, and may include stack canary protections or other runtime safeguards that prevent the exploitation of freed memory references. The fix applies across all supported Apple platforms, indicating a coordinated patch strategy that addresses the root cause rather than individual platform-specific implementations.
Organizations should prioritize immediate deployment of these security updates across all affected devices to mitigate potential exploitation risks. System administrators should monitor for any signs of unusual application behavior or crashes following update installation, as the memory management improvements may introduce subtle changes in how certain web content is handled. The vulnerability's classification under memory safety standards means that organizations should also review their web content filtering policies and user training programs to reduce exposure to malicious web content. Regular security assessments should verify that all Apple platform components are updated to the latest versions, particularly in environments where users may encounter untrusted web content or where compliance requirements mandate specific security controls.
Security teams should consider implementing network-based detection measures to identify attempts to exploit this vulnerability through malformed web requests, though such detection would be challenging given the nature of use-after-free conditions. The remediation approach taken by Apple aligns with industry best practices for memory safety vulnerabilities and demonstrates the importance of continuous security improvements in browser software. Organizations should also maintain awareness of similar vulnerabilities in other browser implementations and ensure their patch management processes are robust enough to address such critical memory safety issues promptly.