CVE-2023-4057: 
NixOS vulnerability analysis and mitigation

CVE-2023-4057 is a high-impact memory safety vulnerability discovered in Firefox 115, Firefox ESR 115.0, and Thunderbird 115.0. The vulnerability was identified by the Mozilla Fuzzing Team and disclosed on August 1, 2023. The affected software versions include Firefox < 116, Firefox ESR < 115.1, and Thunderbird < 115.1 (Mozilla Advisory).

The vulnerability involves memory safety bugs that showed evidence of memory corruption. The issue specifically relates to a missing post barrier in JIT code, where a race condition exists between the barrier and store operations when handling dense elements. The vulnerability received a CVSS v3.1 base score of 9.8 CRITICAL (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H) (NVD).

The memory corruption issues could potentially be exploited to run arbitrary code. The vulnerability affects multiple Mozilla products including Firefox, Firefox ESR, and Thunderbird. While the impact is considered high, in Thunderbird's case, these flaws cannot be exploited through email since scripting is disabled when reading mail, but remain potential risks in browser or browser-like contexts (Mozilla Advisory).

The vulnerability has been fixed in Firefox 116, Firefox ESR 115.1, and Thunderbird 115.1. Users are advised to upgrade to these versions or later to receive the security fixes. The fix involved simplifying the post barrier for MStoreElementHole and MArrayPush operations (Mozilla Advisory).