CVE-2020-1400: Jet Database Engine Remote Code Execution Vulnerability

CVE-2020-1400 is a remote code execution vulnerability in Jet Database Engine, rated Important by Microsoft, with a CVSS 3.0 base score of 7.8 (High). An attacker can exploit it by an attacker with local access, without any privileges and only if a user takes an action. Microsoft has not reported exploitation in the wild and rates exploitation as less likely. The EPSS model estimates a 23.73% probability of exploitation activity in the next 30 days, higher than 98% of all scored vulnerabilities. Microsoft released the fix on 14 July 2020 in the July 2020 Patch Tuesday, delivered through 15 security updates (KB4565503, KB4565489, KB4558998, KB4565483 and more). It affects 44 products in 2 product families (Windows, ESU).

Key facts

CVE ID: CVE-2020-1400
Severity: High CVSS 7.8
Microsoft severity: Important
Impact: Remote Code Execution
Exploited in the wild: No
Publicly disclosed: No
Exploitation likelihood: Less Likely
Weakness: CWE-191
EPSS: 23.73% (percentile 98%)
CISA KEV: Not listed
Released: 14 July 2020
Last updated: 14 July 2020
Patch Tuesday: July 2020 Patch Tuesday
Product families: Windows, ESU

CVSS score and vector

Microsoft scores CVE-2020-1400 at 7.8 (temporal 7) using CVSS 3.0. Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:P/RL:O/RC:C

Metric	Value
Attack vector	Local
Attack complexity	Low
Privileges required	None
User interaction	Required
Scope	Unchanged
Confidentiality impact	High
Integrity impact	High
Availability impact	High
Exploit code maturity	Proof of concept
Remediation level	Official fix
Report confidence	Confirmed

NVD scores it 7.8 (HIGH) with CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

Description

A remote code execution vulnerability exists when the Windows Jet Database 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 Windows Jet Database Engine handles objects in memory.

Affected products (44)

Windows

Product	Security update	Type	Restart
Windows 10 Version 2004 for 32-bit Systems	KB4565503	Security Update	Yes
Windows 10 Version 2004 for ARM64-based Systems	KB4565503	Security Update	Yes
Windows 10 Version 2004 for x64-based Systems	KB4565503	Security Update	Yes
Windows Server, version 2004 (Server Core installation)	KB4565503	Security Update	Yes
Windows 10 Version 1803 for 32-bit Systems	KB4565489	Security Update	Yes
Windows 10 Version 1803 for x64-based Systems	KB4565489	Security Update	Yes
Windows 10 Version 1803 for ARM64-based Systems	KB4565489	Security Update	Yes
Windows 10 Version 1809 for 32-bit Systems	KB4558998	Security Update	Yes
Windows 10 Version 1809 for x64-based Systems	KB4558998	Security Update	Yes
Windows 10 Version 1809 for ARM64-based Systems	KB4558998	Security Update	Yes
Windows Server 2019	KB4558998	Security Update	Yes
Windows Server 2019 (Server Core installation)	KB4558998	Security Update	Yes
Windows 10 Version 1909 for 32-bit Systems	KB4565483	Security Update	Yes
Windows 10 Version 1909 for x64-based Systems	KB4565483	Security Update	Yes
Windows 10 Version 1909 for ARM64-based Systems	KB4565483	Security Update	Yes
Windows Server, version 1909 (Server Core installation)	KB4565483	Security Update	Yes
Windows 10 Version 1709 for 32-bit Systems	KB4565508	Security Update	Yes
Windows 10 Version 1709 for x64-based Systems	KB4565508	Security Update	Yes
Windows 10 Version 1709 for ARM64-based Systems	KB4565508	Security Update	Yes
Windows 10 Version 1903 for 32-bit Systems	KB4565483	Security Update	Yes
Windows 10 Version 1903 for x64-based Systems	KB4565483	Security Update	Yes
Windows 10 Version 1903 for ARM64-based Systems	KB4565483	Security Update	Yes
Windows Server, version 1903 (Server Core installation)	KB4565483	Security Update	Yes
Windows 10 for 32-bit Systems	KB4565513	Security Update	Yes
Windows 10 for x64-based Systems	KB4565513	Security Update	Yes
Windows 10 Version 1607 for 32-bit Systems	KB4565511	Security Update	Yes
Windows 10 Version 1607 for x64-based Systems	KB4565511	Security Update	Yes
Windows Server 2016	KB4565511	Security Update	Yes
Windows Server 2016 (Server Core installation)	KB4565511	Security Update	Yes
Windows 8.1 for 32-bit systems	KB4565541 KB4565540	Monthly Rollup Security Only	Yes Yes
Windows 8.1 for x64-based systems	KB4565541 KB4565540	Monthly Rollup Security Only	Yes Yes
Windows RT 8.1	KB4565541	Monthly Rollup	Yes
Windows Server 2012	KB4565537 KB4565535	Monthly Rollup Security Only	Yes Yes
Windows Server 2012 (Server Core installation)	KB4565537 KB4565535	Monthly Rollup Security Only	Yes Yes
Windows Server 2012 R2	KB4565541 KB4565540	Monthly Rollup Security Only	Yes Yes
Windows Server 2012 R2 (Server Core installation)	KB4565541 KB4565540	Monthly Rollup Security Only	Yes Yes

ESU

Product	Security update	Type	Restart
Windows 7 for 32-bit Systems Service Pack 1	KB4565524 KB4565539	Monthly Rollup Security Only	Yes Yes
Windows 7 for x64-based Systems Service Pack 1	KB4565524 KB4565539	Monthly Rollup Security Only	Yes Yes
Windows Server 2008 for 32-bit Systems Service Pack 2	KB4565536 KB4565529	Monthly Rollup Security Only	Yes Yes
Windows Server 2008 for 32-bit Systems Service Pack 2 (Server Core installation)	KB4565536 KB4565529	Monthly Rollup Security Only	Yes Yes
Windows Server 2008 for x64-based Systems Service Pack 2	KB4565536 KB4565529	Monthly Rollup Security Only	Yes Yes
Windows Server 2008 for x64-based Systems Service Pack 2 (Server Core installation)	KB4565536 KB4565529	Monthly Rollup Security Only	Yes Yes
Windows Server 2008 R2 for x64-based Systems Service Pack 1	KB4565524 KB4565539	Monthly Rollup Security Only	Yes Yes
Windows Server 2008 R2 for x64-based Systems Service Pack 1 (Server Core installation)	KB4565524 KB4565539	Monthly Rollup Security Only	Yes Yes

Security updates (15)

KB4565503 (Security Update)
KB4565489 (Security Update)
KB4558998 (Security Update)
KB4565483 (Security Update)
KB4565508 (Security Update)
KB4565513 (Security Update)
KB4565511 (Security Update)
KB4565524 (Monthly Rollup)
KB4565539 (Security Only)
KB4565541 (Monthly Rollup)
KB4565540 (Security Only)
KB4565536 (Monthly Rollup)
KB4565529 (Security Only)
KB4565537 (Monthly Rollup)
KB4565535 (Security Only)

NIST NVD data

NVD status: Modified
NVD CVSS: 7.8 (HIGH)
NVD weakness: CWE-191
Published to NVD: 14 July 2020
NVD last modified: 17 June 2026

Affected configurations (CPE)

Product	Vulnerable versions
windows 10	all listed versions
windows 10 1607	all listed versions
windows 10 1709	all listed versions
windows 10 1803	all listed versions
windows 10 1809	all listed versions
windows 10 1903	all listed versions
windows 10 1909	all listed versions
windows 10 2004	all listed versions
windows 7	all listed versions
windows 8.1	all listed versions
windows rt 8.1	all listed versions
windows server 2008	all listed versions
windows server 2008 r2 (x64)	all listed versions
windows server 2012	all listed versions
windows server 2012 r2	all listed versions
windows server 2016	all listed versions
windows server 2016 1903	all listed versions
windows server 2016 1909	all listed versions
windows server 2016 2004	all listed versions
windows server 2019	all listed versions

References

https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1400 (Patch, Vendor Advisory)
https://www.zerodayinitiative.com/advisories/ZDI-20-924/ (Third Party Advisory, VDB Entry)
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-1400 (Patch, Vendor Advisory)
https://www.zerodayinitiative.com/advisories/ZDI-20-924/ (Third Party Advisory, VDB Entry)

Acknowledgments

Revision history

Version	Date	Description
1.0	14 July 2020	Information published.