Untrusted search path vulnerability in Self-extracting archive files created by IExpress bundled with Microsoft Windows allows an attacker to gain privileges via a Trojan horse DLL in an unspecified directory.
https://msrc.microsoft.com/blog/2018/04/triaging-a-dll-planting-vulnerability/
https://blogs.technet.microsoft.com/srd/2018/04/04/triaging-a-dll-planting-vulnerability/