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Vulnerability DatabaseCVE-2021-4192

CVE-2021-4192: 
NixOS vulnerability analysis and mitigation

Overview

CVE-2021-4192 is a Use After Free vulnerability discovered in vim text editor. The vulnerability was disclosed on December 31, 2021, affecting vim versions up to 8.2.3949. The issue was found in the win_linetabsize() functionality (NVD, Debian).

Technical details

The vulnerability is classified as a Use After Free issue with a CVSS v3.1 base score of 7.8 (HIGH) with vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. The issue occurs in the win_linetabsize() function where memory is accessed after being freed, potentially leading to arbitrary code execution (NVD, Huntr).

Impact

The vulnerability could allow an attacker to cause unexpected application termination or potentially execute arbitrary code. The issue requires user interaction to exploit, as it involves processing specially crafted input (NVD).

Mitigation and workarounds

The vulnerability was patched in vim version 8.2.3949 with a fix that improves memory handling. The patch involves getting the line again after getvvcol() to prevent the use-after-free condition (Vim Patch). Multiple operating system vendors have released security updates including Apple, Debian, and Fedora (Apple Security, Debian LTS, Fedora).

Additional resources

Source: This report was generated using AI

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