CVE-2020-26968: 
NixOS vulnerability analysis and mitigation

CVE-2020-26968 is a high-impact memory safety vulnerability discovered in Mozilla Firefox 82, Firefox ESR 78.4, and Thunderbird 78.4. The vulnerability was disclosed on November 17, 2020, and affects multiple Mozilla products including Firefox < 83, Firefox ESR < 78.5, and Thunderbird < 78.5. This security issue was identified by Mozilla developers Steve Fink, Jason Kratzer, Randell Jesup, Christian Holler, and Byron Campen (Mozilla Advisory).

The vulnerability is classified as a memory safety bug that showed evidence of memory corruption. The issue received a CVSS v3.1 base score of 8.8 (HIGH) with the vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. Under CVSS v2.0, it scored 9.3 (HIGH) with the vector (AV:N/AC:M/Au:N/C:C/I:C/A:C). The vulnerability is associated with CWE-787 (Out-of-bounds Write) (NVD).

The memory safety bugs demonstrated evidence of memory corruption that could potentially be exploited to execute arbitrary code on affected systems. With sufficient effort, these vulnerabilities could be leveraged to compromise system security and run malicious code (Mozilla Advisory).

The vulnerability was addressed in Firefox 83, Firefox ESR 78.5, and Thunderbird 78.5. Users should upgrade to these versions or later to mitigate the risk. For Thunderbird users, while the risk through email is minimal due to disabled scripting, updating to version 78.5 or later is recommended (Red Hat).