CVE-2024-20677
CVE-2024-20677 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-122.
Key facts
- Severity: High (CVSS 3.x base score 7.8)
- EPSS exploit prediction: 3% (87th percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2024-18392
- Weakness: CWE-122
- Affected product: Microsoft 365 Apps
- Published:
- Last modified:
Description
A security vulnerability exists in FBX that could lead to remote code execution. To mitigate this vulnerability, the ability to insert FBX files has been disabled in Word, Excel, PowerPoint and Outlook for Windows and Mac. Versions of Office that had this feature enabled will no longer have access to it. This includes Office 2019, Office 2021, Office LTSC for Mac 2021, and Microsoft 365. As of February 13, 2024, the ability to insert FBX files has also been disabled in 3D Viewer. 3D models in Office documents that were previously inserted from a FBX file will continue to work as expected unless the Link to File option was chosen at insert time. This change is effective as of the January 9, 2024 security update.
Frequently asked questions
- What is CVE-2024-20677?
- A security vulnerability exists in FBX that could lead to remote code execution. To mitigate this vulnerability, the ability to insert FBX files has been disabled in Word, Excel, PowerPoint and Outlook for Windows and Mac. Versions of Office that had this feature enabled will no longer have access to it. This includes Office 2019, Office 2021, Office LTSC for Mac 2021, and Microsoft 365. As of February 13, 2024, the ability to insert FBX files has also been disabled in 3D Viewer. 3D models in Office documents that were previously inserted from a FBX file will continue to work as expected unless the Link to File option was chosen at insert time. This change is effective as of the January 9, 2024 security update.
- How severe is CVE-2024-20677?
- CVE-2024-20677 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-2024-20677 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (87th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2024-20677?
- CVE-2024-20677 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-2024-20677?
- 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.
- Does CVE-2024-20677 have an EU (EUVD) identifier?
- Yes. CVE-2024-20677 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-18392.
- When was CVE-2024-20677 published?
- CVE-2024-20677 was published on 2024-01-09 and last updated on 2026-06-17.
References
Affected products (4)
- cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:*:*
- cpe:2.3:a:microsoft:office:2019:*:*:*:*:*:*:*
- cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:-:*:*
- cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:*:*:*:*:macos:*:*
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