CVE-2025-43429 is a buffer overflow vulnerability discovered in Apple Safari, identified by the Apple security team and published in November 2025. The vulnerability arises from insufficient bounds checking when processing certain crafted web content, which can lead to a memory corruption condition resulting in an unexpected process crash. This vulnerability affects Safari browsers on multiple Apple platforms, including macOS (Safari 26.1), visionOS 26.1, watchOS 26.1, iOS 26.1, iPadOS 26.1, and tvOS 26.1. The root cause is a classic buffer overflow, where input data exceeds the allocated buffer size, causing memory corruption. Although the primary observed impact is a denial-of-service via process crash, buffer overflows can sometimes be leveraged for more severe exploits such as arbitrary code execution, though no such exploitation has been reported for this CVE. The vulnerability does not require user authentication but does require user interaction in the form of visiting or processing malicious web content. Apple addressed the issue by implementing improved bounds checking to prevent the overflow. No CVSS score was assigned at publication, and no known exploits are currently in the wild. The vulnerability underscores the importance of timely patching of Safari and related Apple OS versions to maintain browser stability and security.

The primary impact of CVE-2025-43429 is on the availability of the Safari browser, as processing maliciously crafted web content can cause unexpected process crashes, resulting in denial-of-service conditions. For European organizations, this can disrupt business operations relying on Safari for web access, especially in sectors where Apple devices are prevalent, such as creative industries, education, and mobile workforce environments. While no evidence currently suggests exploitation beyond crashes, the buffer overflow nature of the vulnerability means there is a potential risk for escalation to code execution if further exploit development occurs. This could compromise confidentiality and integrity if exploited. The disruption could affect web-based applications, internal portals, or cloud services accessed via Safari. Additionally, organizations with Bring Your Own Device (BYOD) policies may face increased risk due to inconsistent patching. The impact is heightened in critical infrastructure sectors and government agencies where browser stability and security are paramount. The lack of known exploits provides a window for proactive mitigation before attackers potentially weaponize the flaw.

To mitigate CVE-2025-43429, European organizations should immediately prioritize updating all Apple devices to Safari 26.1 or the corresponding OS versions (visionOS 26.1, watchOS 26.1, iOS 26.1, iPadOS 26.1, tvOS 26.1) where the vulnerability is fixed. Organizations should enforce patch management policies that include Apple ecosystem devices and verify compliance through endpoint management tools. Network-level protections such as web filtering and intrusion prevention systems can be tuned to block or flag suspicious web content that could exploit this vulnerability. User awareness campaigns should educate employees about the risks of visiting untrusted websites and the importance of applying updates promptly. For critical environments, consider restricting Safari usage or employing alternative browsers until patches are applied. Monitoring browser crash logs and unusual network activity can help detect attempted exploitation. Additionally, organizations should review and tighten web content security policies, including Content Security Policy (CSP) headers, to reduce exposure to malicious web content. Collaboration with Apple support channels can provide further guidance and early warnings of emerging exploits.