CVE-2020-16947: A remote code execution vulnerability exists in Microsoft Outlook software when the software fails to properly handle objects in memory. An attacker who…

PriorityP263high8.8CVSS 3.1

AVNACLPRNUIRSUCHIHAH

EPSS

33.55%

98.2th percentile

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. 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. Note that where severity is indicated as Critical in the Affected Products table, the Preview Pane is an attack vector. The security update addresses the vulnerability by correcting how Outlook handles objects in memory.

Affected

10 ranges

Vendor	Product	Version range	Fixed in
microsoft	microsoft_365_apps_for_enterprise	>= 16.0.1 < https://aka.ms/OfficeSecurityReleases	https://aka.ms/OfficeSecurityReleases
microsoft	microsoft_office_2019	>= 19.0.0 < https://aka.ms/OfficeSecurityReleases	https://aka.ms/OfficeSecurityReleases
microsoft	microsoft_outlook_2016	>= 16.0.0.0 < publication	publication
microsoft	office	—	—
microsoft	outlook	—	—
msrc	microsoft_365_apps_for_enterprise_for_32-bit_systems	—	—
msrc	microsoft_365_apps_for_enterprise_for_64-bit_systems	—	—
msrc	microsoft_office_2019_for_32-bit_editions	—	—
msrc	microsoft_office_2019_for_64-bit_editions	—	—
msrc	microsoft_outlook_2016	—	—

Detection & IOCsextracted from sources · hover to see the quote

→Flag inbound emails containing specially crafted file attachments targeting Microsoft Outlook; the exploit requires delivery of a malformed/crafted file via email or web link. ↗
→Monitor Outlook processes for anomalous child process spawning or memory object handling failures, consistent with exploitation of improper in-memory object handling. ↗

·Severity is rated Critical only for product versions where the Preview Pane is listed as an attack vector in the Affected Products table; other versions may carry a lower severity rating. ↗
·As of the patch release date, the vulnerability had not been publicly disclosed or exploited in the wild, reducing immediate urgency but not eliminating risk. ↗

CVSS provenance

nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

nvdv2.09.3CRITICALAV:N/AC:M/Au:N/C:C/I:C/A:C

vendor_msrc7.5HIGH

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