CVE-2026-42171
CVE-2026-42171
NSIS (Nullsoft Scriptable Install System) 3.06.1 before 3.12 sometimes uses the Low IL temp directory when executing as SYSTEM, allowing local attackers to gain privileges (if they can cause my_GetTempFileName to return 0, as shown in the references).
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Affected products
Nullsoft · Nullsoft Scriptable Install SystemWant to know if your infrastructure is exposed to this?
Talk to TrueHacking →References
https://github.com/NSIS-Dev/nsis/blob/7359413009afd4f0fff472d841fc2f2cc0e0a5f8/Source/exehead/util.c#L475-L484https://github.com/NSIS-Dev/nsis/commit/8e6f02205d5f22da6c7855dbfe59b2af667330cahttps://learn.microsoft.com/en-us/windows/win32/api/winbase/nf-winbase-gettempfilenamehttps://nsis.sourceforge.io/Docs/AppendixF.html#v3.12-cl