cbcvebase.
CVE-2021-38646
published 2021-09-15

CVE-2021-38646: Microsoft Office Access Connectivity Engine Remote Code Execution Vulnerability

PriorityP184high7.8CVSS 3.1
AVLACLPRNUIRSUCHIHAH
KEVITWRansomware
CISA Known Exploited Vulnerabilitydue 2022-04-18
Exploited in the wild
EPSS
4.40%
90.3th percentile
Microsoft Office Access Connectivity Engine Remote Code Execution Vulnerability

Affected

14 ranges
VendorProductVersion rangeFixed in
microsoftmicrosoft_365_apps_for_enterprise>= 16.0.1 < https://aka.ms/OfficeSecurityReleaseshttps://aka.ms/OfficeSecurityReleases
microsoftmicrosoft_office_2013_service_pack_1>= 15.0.0 < 5381.10005381.1000
microsoftmicrosoft_office_2016>= 16.0.0 < 5215.10005215.1000
microsoftmicrosoft_office_2019>= 19.0.0 < https://aka.ms/OfficeSecurityReleaseshttps://aka.ms/OfficeSecurityReleases
microsoftoffice
microsoftoffice
microsoftoffice
msrcmicrosoft_365_apps_for_enterprise_for_32-bit_systems
msrcmicrosoft_365_apps_for_enterprise_for_64-bit_systems
msrcmicrosoft_office_2013_rt_service_pack_1
msrcmicrosoft_office_2013_service_pack_1
msrcmicrosoft_office_2016
msrcmicrosoft_office_2019_for_32-bit_editions
msrcmicrosoft_office_2019_for_64-bit_editions

Detection & IOCsextracted from sources · hover to see the quote

  • Preview Pane is NOT an attack vector; user interaction (opening a malicious Access file) is required for exploitation
  • Affected component is Microsoft Office Access Connectivity Engine (ACE); monitor for suspicious Access database file opens or ACE engine process activity
  • ·Exploitation likelihood is rated 'Less Likely' for both latest and older software releases as of advisory publication; however, CISA added this to the Known Exploited Vulnerabilities catalog with a remediation due date, indicating elevated real-world risk
  • ·No public exploit or active exploitation confirmed at time of Microsoft advisory, but CISA mandated remediation by 2022-04-18

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
nvdv2.06.8MEDIUMAV:N/AC:M/Au:N/C:P/I:P/A:P
vulncheck7.8HIGH
cisa7.8HIGH
vendor_msrc7.8HIGH
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