CVE-2026-42171 | BDVDB-2026-329007 Detail
NullsoftNullsoft Scriptable Install System
Description#
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).
Impact#
Per CVSS v3.1: confidentiality impact high, integrity impact high, availability impact high. Attack vector: local.
Weaknesses#
- CWE-427 Uncontrolled Search Path Element
References#
- https://nsis.sourceforge.io/Docs/AppendixF.html#v3.12-cl
- https://github.com/NSIS-Dev/nsis/commit/8e6f02205d5f22da6c7855dbfe59b2af667330ca
- https://github.com/NSIS-Dev/nsis/blob/7359413009afd4f0fff472d841fc2f2cc0e0a5f8/Source/exehead/util.c#L475-L484
- https://learn.microsoft.com/en-us/windows/win32/api/winbase/nf-winbase-gettempfilename
Exploit#
No public exploit known
History#
- Version 1Record published in the CVE List.
- Version 2Most recent update recorded in the CVE List.