CVE-2021-42296
CVE-2021-42296 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. The underlying weakness is classified as CWE-94.
Key facts
- Severity: High (CVSS 3.x base score 7.8)
- CVSS v2: 6.9
- EPSS exploit prediction: 1% (64th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-94
- Affected product: Microsoft 365 Apps
- Published:
- Last modified:
Description
Microsoft Word Remote Code Execution Vulnerability
Frequently asked questions
- What is CVE-2021-42296?
- Microsoft Word Remote Code Execution Vulnerability
- How severe is CVE-2021-42296?
- CVE-2021-42296 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-2021-42296 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (64th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-42296?
- CVE-2021-42296 primarily affects Microsoft 365 Apps. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-42296?
- 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-2021-42296 published?
- CVE-2021-42296 was published on 2021-11-10 and last updated on 2026-08-19.
References
- https://msrc.microsoft.com/update-guide/vulnerability/CVE-2021-42296
- https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2021-42296
Affected products (4)
- cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x64:*
- cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x86:*
- cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:*:x64:*
- cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:*:x86:*
More vulnerabilities in Microsoft 365 Apps
- CVE-2026-78509 — Critical (CVSS 9.8): Heap-based buffer overflow in Microsoft Office Outlook allows an unauthorized attacker to execute code over a network.
- CVE-2024-21413 — Critical (CVSS 9.8): Microsoft Outlook Remote Code Execution Vulnerability
- CVE-2023-23397 — Critical (CVSS 9.8): Microsoft Outlook Elevation of Privilege Vulnerability
- CVE-2020-0901 — Critical (CVSS 9.8): A remote code execution vulnerability exists in Microsoft Excel software when the software fails to properly handle…
- CVE-2023-33150 — Critical (CVSS 9.6): Microsoft Office Security Feature Bypass Vulnerability
- CVE-2026-70125 — High (CVSS 8.8): Microsoft Office Outlook Remote Code Execution Vulnerability
All CVEs affecting Microsoft 365 Apps →
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