SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2021-38646

Microsoft Office Access Connectivity Engine Remote Code Execution Vulnerability

KEVHIGH 7.8EPSS 7.99%

Does this matter?

Known to be exploited in the wild (CISA KEV, CISA remediation deadline 18 April 2022). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.

Description

Microsoft Office Access Connectivity Engine Remote Code Execution Vulnerability

CVSS 3.1
7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
EPSS
7.99% probability · 94th percentile
CISA KEV
Listed 28 March 2022 · due 18 April 2022 · used in ransomware campaigns
Affected
microsoft/365 apps · microsoft/office · microsoft/office 2016 · microsoft/office 2019
Source
secure@microsoft.com

CISA notes

Apply updates per vendor instructions. https://nvd.nist.gov/vuln/detail/CVE-2021-38646

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.