CVE-2020-28599: 
NixOS vulnerability analysis and mitigation

A stack-based buffer overflow vulnerability exists in the import_stl.cc:import_stl() functionality of Openscad openscad-2020.12-RC2. The vulnerability, identified as CVE-2020-28599, was discovered in February 2021 and affects the STL file parsing functionality in OpenSCAD, a software for creating solid 3D CAD objects (NVD, Talos).

The vulnerability occurs in the import_stl() function when processing STL files. When parsing vertex coordinates in STL files, the code uses a fixed-size array double vdata[3][3] but fails to properly validate array bounds, leading to a stack-based buffer overflow. The CVSS v3.1 base score is 7.8 HIGH (Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H) according to NVD, while Talos rates it at 8.8 HIGH (Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H) (NVD, Talos).

A specially crafted STL file can lead to code execution with the privileges of the process or cause a Denial of Service condition. The vulnerability requires user interaction in the form of loading a malicious STL file into OpenSCAD (Gentoo, Talos).

The vulnerability can be triggered by providing a malicious STL file to an OpenSCAD user. Proof-of-concept exploit code has been developed by security researchers, demonstrating the potential for arbitrary code execution (Talos).

Users should upgrade to OpenSCAD version 2021.01 or later which contains the fix for this vulnerability. Various Linux distributions have also released security updates to address this issue (Gentoo, Fedora).