CVE-2023-37420: 
NixOS vulnerability analysis and mitigation

Multiple out-of-bounds write vulnerabilities exist in the VCD parse_valuechange portdump functionality of GTKWave 3.3.115. A specially crafted .vcd file can lead to arbitrary code execution. A victim would need to open a malicious file to trigger these vulnerabilities. This vulnerability specifically concerns the out-of-bounds write when triggered via the vcd2lxt conversion utility (Talos).

The vulnerability exists in the vcd2lxt conversion utility of GTKWave. The issue occurs in the parse_valuechange function where there is an incorrect buffer size check that allows a NULL byte out-of-bounds write in the heap. The vulnerability has a CVSS 3.1 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 vulnerability is classified as CWE-787 (Out-of-bounds Write) (NVD, Talos).

If successfully exploited, this vulnerability could allow an attacker to execute arbitrary code on the targeted system. The attack requires user interaction as the victim needs to open a specially crafted malicious file (Talos).

The vulnerability has been fixed in GTKWave version 3.3.118. Users are advised to upgrade to this version or later. The fix has been included in various distribution updates including Debian 10 (buster) version 3.3.98+really3.3.118-0+deb10u1 (Debian LTS).