Vulnerability · Published Oct 16, 2020 · Assigned by microsoft
CVE-2020-16947Microsoft Outlook Remote Code Execution Vulnerability
High 7.5
In plain English
A high-severity security flaw in Microsoft 365 Apps for Enterprise from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 33.7% (higher than 98% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code.
Official description
<p>A remote code execution vulnerability exists in Microsoft Outlook software when the software fails to properly handle objects in memory. An attacker who successfully exploited the vulnerability could run arbitrary code in the context of the targeted user. If the targeted user is logged on with administrative user rights, an attacker could take control of the affected system. An attacker could then install programs; view, change, or delete data; or create new accounts with full user rights. Users whose accounts are configured to have fewer user rights on the system could be less impacted than users who operate with administrative user rights.</p> <p>Exploitation of the vulnerability requires that a user open a specially crafted file with an affected version of Microsoft Outlook software. In an email attack scenario, an attacker could exploit the vulnerability by sending the specially crafted file to the user and convincing the user to open the file. In a web-based attack scenario, an attacker could host a website (or leverage a compromised website that accepts or hosts user-provided content) that contains a specially crafted file designed to exploit the vulnerability. An attacker would have no way to force users to visit the website. Instead, an attacker would have to convince users to click a link, typically by way of an enticement in an email or instant message, and then convince them to open the specially crafted file.</p> <p>Note that where severity is indicated as Critical in the Affected Products table, the Preview Pane is an attack vector.</p> <p>The security update addresses the vulnerability by correcting how Outlook handles objects in memory.</p>
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Microsoft Office 2019 | 19.0.0 – before https://aka.ms/OfficeSecurityReleases |
| Microsoft | Microsoft 365 Apps for Enterprise | 16.0.1 – before https://aka.ms/OfficeSecurityReleases |
| Microsoft | Microsoft Outlook 2016 | 16.0.0.0 – before publication |
References
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-16947
- https://www.zerodayinitiative.com/advisories/ZDI-20-1250/
- https://www.zerodayinitiative.com/advisories/ZDI-20-1249/
- http://packetstormsecurity.com/files/169961/Microsoft-Outlook-2019-16.0.13231.20262-Remote-Code-Execution.html