CVE-2018-8403

Microsoft Browser Memory Corruption Vulnerability

CVE-2018-8403 is fixed in 26 products on 1 platform, first by KB4343887, released August 14, 2018. It is not reported as exploited, but the vendor rates exploitation more likely. Patch Radar priority: Urgent.

Urgent
CVSS
4.2
Moderate
Exploitation
More likely
Vendor assessment
CISA KEV
Not listed
Not in the Known Exploited Vulnerabilities catalog
EPSS
0.1337
96th percentile

<p>A remote code execution vulnerability exists in the way that Microsoft browsers access objects in memory. The vulnerability could corrupt memory in a way that could allow an attacker to execute arbitrary code in the context of the current user. An attacker who successfully exploited the vulnerability could gain the same user rights as the current user. If the current user is logged on with administrative user rights, the attacker could take control of an affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights.</p> <p>An attacker could host a specially crafted website that is designed to exploit the vulnerability through Microsoft browsers, and then convince a user to view the website. The attacker could also take advantage of compromised websites, or websites that accept or host user-provided content or advertisements, by adding specially crafted content that could exploit the vulnerability. In all cases, however, an attacker would have no way to force users to view the attacker-controlled content. Instead, an attacker would have to convince users to take action, typically via an enticement in email or instant message, or by getting them to open an email attachment.</p> <p>The security update addresses the vulnerability by modifying how Microsoft browsers handle objects in memory.</p>

Where it's fixed

ProductFixed inFixReleased
Microsoft
Internet Explorer 10 on Windows Server 2012 KB4343205 Aug 14, 2018
Internet Explorer 10 on Windows Server 2012 KB4343901 Aug 14, 2018
Internet Explorer 11 on Windows 10 Version 1607 for 32-bit Systems 14393.2430 KB4343887 Aug 14, 2018
Internet Explorer 11 on Windows 10 Version 1607 for x64-based Systems 14393.2430 KB4343887 Aug 14, 2018
Internet Explorer 11 on Windows 10 Version 1703 for 32-bit Systems 15063.1266 KB4343885 Aug 14, 2018
Internet Explorer 11 on Windows 10 Version 1703 for x64-based Systems 15063.1266 KB4343885 Aug 14, 2018
Internet Explorer 11 on Windows 10 Version 1709 for 32-bit Systems 16299.611 KB4343897 Aug 14, 2018
Internet Explorer 11 on Windows 10 Version 1709 for x64-based Systems 16299.611 KB4343897 Aug 14, 2018
Internet Explorer 11 on Windows 10 Version 1803 for 32-bit Systems 17134.228 KB4343909 Aug 14, 2018
Internet Explorer 11 on Windows 10 Version 1803 for x64-based Systems 17134.228 KB4343909 Aug 14, 2018
Internet Explorer 11 on Windows 10 for 32-bit Systems 10240.17946 KB4343892 Aug 14, 2018
Internet Explorer 11 on Windows 10 for x64-based Systems 10240.17946 KB4343892 Aug 14, 2018
Internet Explorer 11 on Windows 7 for 32-bit Systems Service Pack 1 KB4343900 Aug 14, 2018
Internet Explorer 11 on Windows 7 for 32-bit Systems Service Pack 1 KB4343205 Aug 14, 2018
Internet Explorer 11 on Windows 7 for x64-based Systems Service Pack 1 KB4343900 Aug 14, 2018
Internet Explorer 11 on Windows 7 for x64-based Systems Service Pack 1 KB4343205 Aug 14, 2018
Internet Explorer 11 on Windows 8.1 for 32-bit systems KB4343205 Aug 14, 2018
Internet Explorer 11 on Windows 8.1 for 32-bit systems KB4343898 Aug 14, 2018
Internet Explorer 11 on Windows 8.1 for x64-based systems KB4343205 Aug 14, 2018
Internet Explorer 11 on Windows 8.1 for x64-based systems KB4343898 Aug 14, 2018
Internet Explorer 11 on Windows RT 8.1 KB4343898 Aug 14, 2018
Internet Explorer 11 on Windows Server 2008 R2 for x64-based Systems Service Pack 1 KB4343900 Aug 14, 2018
Internet Explorer 11 on Windows Server 2008 R2 for x64-based Systems Service Pack 1 KB4343205 Aug 14, 2018
Internet Explorer 11 on Windows Server 2012 R2 KB4343205 Aug 14, 2018
Internet Explorer 11 on Windows Server 2012 R2 KB4343898 Aug 14, 2018
Internet Explorer 11 on Windows Server 2016 14393.2430 KB4343887 Aug 14, 2018
Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1607 for 32-bit Systems 14393.2430 KB4343887 Aug 14, 2018
Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1607 for x64-based Systems 14393.2430 KB4343887 Aug 14, 2018
Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1703 for 32-bit Systems 15063.1266 KB4343885 Aug 14, 2018
Microsoft Edge (EdgeHTML-based) on Windows 10 Version 1703 for x64-based Systems 15063.1266 KB4343885 Aug 14, 2018
Microsoft Edge (EdgeHTML-based) on Windows 10 for 32-bit Systems 10240.17946 KB4343892 Aug 14, 2018
Microsoft Edge (EdgeHTML-based) on Windows 10 for x64-based Systems 10240.17946 KB4343892 Aug 14, 2018
Microsoft Edge (EdgeHTML-based) on Windows Server 2016 14393.2430 KB4343887 Aug 14, 2018