CVE intelligence and bounded remediation

CVE-2018-8420 — Microsoft Windows 10 security vulnerability

High CVSS 9.3

A remote code execution vulnerability exists when the Microsoft XML Core Services MSXML parser processes user input, aka "MS XML Remote Code Execution Vulnerability." This affects Windows 7, Windows Server 2012 R2, Windows RT 8.1, Windows Server 2008, Windows Server 2012, Windows 8.1, Windows Server 2016, Windows Server 2008 R2, Windows 10, Windows 10 Servers.

Severity
High
CVSS
9.3 (2.0)
Published
2018-09-13
CISA KEV
Not currently listed
Ecosystem
windows/system
Weaknesses
CWE-611

Affected products

  • microsoft / windows_10
  • microsoft / windows_10 / 1607
  • microsoft / windows_10 / 1703
  • microsoft / windows_10 / 1709
  • microsoft / windows_10 / 1803
  • microsoft / windows_7

Showing 6 representative product identities from 16 source matches. Confirm exact affected versions with the linked vendor and NVD evidence.

Matched remediation archetype

XML external entity and unsafe XML processing

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Inventory XML parsers used by APIs, file imports, office or image formats, identity protocols, feeds, and background jobs.
  • Determine whether document type declarations, external entities, XInclude, schemas, or network resolvers are enabled.
  • Map parser filesystem and network access and the sensitivity of documents it processes.

Remediate safely

  • Configure each parser to reject document type declarations and disable external entity, XInclude, and network resolution features.
  • Prefer a data format or hardened parser that does not support external resolution, and apply input size and depth limits.
  • Update affected XML libraries and centralize secure parser construction so callers cannot silently override it.

Authoritative sources

Complete CVE record and remediation plan

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