CVE-2019-0948: Microsoft Windows Event Viewer XML External Entity Processing Information Disclosure Vulnerability

An information disclosure vulnerability exists in the Windows Event Viewer (eventvwr.msc) when it improperly parses XML input containing a reference to an external entity. An attacker who successfully exploited this vulnerability could read arbitrary files via an XML external entity (XXE) declaration. To exploit the vulnerability, an attacker could create a file containing specially crafted XML content and convince an authenticated user to import the file. The update addresses the vulnerability by modifying the way that the Event Viewer parses XML input.

— Microsoft

This vulnerability allows remote attackers to disclose sensitive information on affected installations of Microsoft Windows. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within Event Viewer. Due to the improper restriction of XML External Entity (XXE) references, a specially crafted document specifying a URI causes the XML parser to access the URI and embed the contents back into the XML document for further processing. An attacker can leverage this vulnerability to disclose the contents of files in the context of the current user.

— ZDI