CVE-2020-16855
CVE-2020-16855 is a medium-severity vulnerability in Microsoft Office with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-125.
Key facts
- Severity: Medium (CVSS 3.x base score 5.5)
- CVSS v2: 4.3
- EPSS exploit prediction: 4% (90th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-125
- Affected product: Microsoft Office
- Published:
- Last modified:
Description
<p>An information disclosure vulnerability exists when Microsoft Office software reads out of bound memory due to an uninitialized variable, which could disclose the contents of memory. An attacker who successfully exploited the vulnerability could view out of bound memory.</p> <p>Exploitation of the vulnerability requires that a user open a specially crafted file with an affected version of Microsoft Office software.</p> <p>The security update addresses the vulnerability by properly initializing the affected variable.</p>
Frequently asked questions
- What is CVE-2020-16855?
- <p>An information disclosure vulnerability exists when Microsoft Office software reads out of bound memory due to an uninitialized variable, which could disclose the contents of memory. An attacker who successfully exploited the vulnerability could view out of bound memory.</p> <p>Exploitation of the vulnerability requires that a user open a specially crafted file with an affected version of Microsoft Office software.</p> <p>The security update addresses the vulnerability by properly initializing the affected variable.</p>
- How severe is CVE-2020-16855?
- CVE-2020-16855 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity none, and availability none.
- Is CVE-2020-16855 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 4% (90th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-16855?
- CVE-2020-16855 primarily affects Microsoft Office. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2020-16855?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2020-16855 published?
- CVE-2020-16855 was published on 2020-09-11 and last updated on 2026-06-17.
References
Affected products (2)
- cpe:2.3:a:microsoft:office:2016:*:*:*:*:macos:*:*
- cpe:2.3:a:microsoft:office:2019:*:*:*:*:macos:*:*
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