Microsoft Office 365 Apps for Enterprise/2019 Access Connectivity Engine memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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7.1$0-$5k0.00

Summaryinfo

A vulnerability was found in Microsoft Office 365 Apps for Enterprise/2019 and classified as critical. This vulnerability affects unknown code of the component Access Connectivity Engine. Such manipulation leads to memory corruption. This vulnerability is uniquely identified as CVE-2020-16957. The attack can be launched remotely. No exploit exists. It is advisable to implement a patch to correct this issue.

Detailsinfo

A vulnerability was found in Microsoft Office 365 Apps for Enterprise/2019 (Office Suite Software) and classified as critical. Affected by this issue is an unknown code of the component Access Connectivity Engine. The manipulation with an unknown input leads to a memory corruption vulnerability. Using CWE to declare the problem leads to CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. Impacted is confidentiality, integrity, and availability. CVE summarizes:

<p>A remote code execution vulnerability exists when the Microsoft Office Access Connectivity Engine improperly handles objects in memory. An attacker who successfully exploited this vulnerability could execute arbitrary code on a victim system.</p> <p>An attacker could exploit this vulnerability by enticing a victim to open a specially crafted file.</p> <p>The update addresses the vulnerability by correcting the way the Microsoft Office Access Connectivity Engine handles objects in memory.</p>

The weakness was disclosed 10/13/2020 as confirmed security guidance (Website). The advisory is shared for download at portal.msrc.microsoft.com. This vulnerability is handled as CVE-2020-16957. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. There are neither technical details nor an exploit publicly available. The advisory points out:

A remote code execution vulnerability exists when the Microsoft Office Access Connectivity Engine improperly handles objects in memory. An attacker who successfully exploited this vulnerability could execute arbitrary code on a victim system. An attacker could exploit this vulnerability by enticing a victim to open a specially crafted file. The update addresses the vulnerability by correcting the way the Microsoft Office Access Connectivity Engine handles objects in memory.

It is declared as proof-of-concept.

Applying a patch is able to eliminate this problem. A possible mitigation has been published immediately after the disclosure of the vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

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Vendor

Name

Version

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Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.4
VulDB Meta Temp Score: 7.1

VulDB Base Score: 6.3
VulDB Temp Score: 5.7
VulDB Vector: 🔍
VulDB Reliability: 🔍

Vendor Base Score (Microsoft): 7.8
Vendor Vector (Microsoft): 🔍

NVD Base Score: 7.8
NVD Vector: 🔍

CNA Base Score: 7.8
CNA Vector: 🔍

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: Partially
Local: Yes
Remote: Yes

Availability: 🔍
Status: Proof-of-Concept

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Patch
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Timelineinfo

08/04/2020 🔍
10/13/2020 +70 days 🔍
10/13/2020 +0 days 🔍
10/14/2020 +0 days 🔍
02/25/2026 +1960 days 🔍

Sourcesinfo

Vendor: microsoft.com

Advisory: portal.msrc.microsoft.com
Status: Confirmed

CVE: CVE-2020-16957 (🔍)
GCVE (CVE): GCVE-0-2020-16957
GCVE (VulDB): GCVE-100-162572

Entryinfo

Created: 10/14/2020 09:41
Updated: 02/25/2026 01:09
Changes: 10/14/2020 09:41 (30), 10/14/2020 09:45 (25), 11/17/2020 08:34 (5), 11/18/2020 23:13 (2), 11/18/2020 23:16 (14), 02/25/2026 01:09 (29)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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