CVE-2020-16957
CVE-2020-16957 is a high-severity vulnerability in Microsoft 365 Apps with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: High (CVSS 3.x base score 7.8)
- CVSS v2: 9.3
- EPSS exploit prediction: 4% (88th percentile)
- Actively exploited: Not listed in CISA KEV
- Affected product: Microsoft 365 Apps
- Published:
- Last modified:
Description
<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>
Frequently asked questions
- What is CVE-2020-16957?
- <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>
- How severe is CVE-2020-16957?
- CVE-2020-16957 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2020-16957 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (88th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-16957?
- CVE-2020-16957 primarily affects Microsoft 365 Apps. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2020-16957?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2020-16957 published?
- CVE-2020-16957 was published on 2020-10-16 and last updated on 2026-06-17.
References
Affected products (2)
- cpe:2.3:a:microsoft:365_apps:-:*:*:*:*:*:*:*
- cpe:2.3:a:microsoft:office:2019:*:*:*:*:-:*:*
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