01 Record
CVE-2021-38646
Microsoft Office Access Connectivity Engine Remote Code Execution Vulnerability
HighKEVPUBLISHEDCNA: microsoft
CNA base score7.8 CVSS v3.xCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
02 Description
Microsoft Office Access Connectivity Engine Remote Code Execution Vulnerability
03 Exploitation and scoring
- Exploitation
- Exploited in the wild. Listed in the CISA Known Exploited Vulnerabilities catalog on 2022-03-28. Federal remediation due 2022-04-18. Known ransomware campaign use: reported by CISA.
- SSVC decision
- ExploitationactiveCISA reports credible evidence of active exploitation.
- AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
- Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.
- EPSS probability
- 7.98% probability of exploitation activity in the next 30 days.
- EPSS percentile
- Equal to or higher than the score of 94.7% of scored records. A rank, not a probability.
- NVD base score
- 7.8 (CVSS v3.x), scored by the NVD independently of the CNA.
- NVD CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- NVD analysis status
- Analyzed. NVD last modified this record on 2026-08-10.
- Red Hat severity
- No Red Hat rating. Red Hat rates the CVEs that affect its products.
Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.
04 Metadata
- Published
- 2021-09-15 11:24Z5 YR AGO
- Last updated
- 2026-08-10 15:11Z2 MO AGO
- Reserved
- 2021-08-13
- Assigning CNA
- microsoft
- Record state
- PUBLISHED
- Severity
- High (CVSS 7.8)
- CNA CVSS vector
- CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
- Weaknesses
- No CWE assigned
- Data version
- 5.2
- Document digest
- d5d0ff7916ebb8e897add4f24b0e1707d04f9e567dfd329edf4443dca1d5f4d9
05 Affected products
VendorProductVersionsPlatforms
MicrosoftMicrosoft 365 Apps for Enterprise16.0.1 to < https://aka.ms/OfficeSecurityReleases32-bit Systems, x64-based Systems
MicrosoftMicrosoft Office 2013 Service Pack 115.0.0 to < 5381.100032-bit Systems, ARM64-based Systems, x64-based Systems
MicrosoftMicrosoft Office 201919.0.0 to < https://aka.ms/OfficeSecurityReleases32-bit Systems, x64-based Systems
06 References
- msrc.microsoft.comMicrosoft Office Access Connectivity Engine Remote Code Execution Vulnerabilityhttps://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-38646
- portal.msrc.microsoft.comhttps://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-38646
- www.cisa.govhttps://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-38646