CVE-2020-3867: 
NixOS vulnerability analysis and mitigation

CVE-2020-3867 is a universal cross-site scripting vulnerability discovered in Apple's software products. The vulnerability was addressed in iOS 13.3.1, iPadOS 13.3.1, tvOS 13.3.1, Safari 13.0.5, iTunes for Windows 12.10.4, iCloud for Windows 11.0, and iCloud for Windows 7.17. The issue was reported by an anonymous researcher and was fixed in January 2020 (Apple Support, CVE Mitre).

The vulnerability stems from a logic issue in the WebKit component that was addressed with improved state management. The vulnerability received a CVSS v3.1 score of AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N, indicating a network-accessible vulnerability requiring user interaction with low complexity and no privileges required (NVD).

When exploited, the vulnerability could allow processing of maliciously crafted web content leading to universal cross-site scripting attacks. This could potentially allow attackers to execute arbitrary scripts in the context of any website, potentially leading to theft of sensitive information or session hijacking (Apple Support).

Apple addressed this vulnerability by implementing improved state management in the affected software versions. Users are advised to update to iOS 13.3.1, iPadOS 13.3.1, tvOS 13.3.1, Safari 13.0.5, iTunes for Windows 12.10.4, iCloud for Windows 11.0, or iCloud for Windows 7.17 depending on their platform (Apple Support).