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CVE-2026-50301 Microsoft CVE debrief

CVE-2026-50301 is a high-severity vulnerability in Microsoft Office, allowing unauthorized attackers to execute code locally via a heap-based buffer overflow. The vulnerability has a CVSS score of 7.8 and is classified as HIGH. Microsoft Office 2016, 2019, 2021, and 2024 are affected, with various architectures and platforms impacted. This vulnerability could allow an attacker to execute arbitrary code on a system, potentially leading to a compromise of sensitive data or disruption of service.

Vendor
Microsoft
Product
Microsoft 365 Apps for Enterprise
CVSS
HIGH 7.8
CISA KEV
Not listed in stored evidence
Original CVE published
2026-07-14
Original CVE updated
2026-07-16
Advisory published
2026-07-14
Advisory updated
2026-07-16

Who should care

Organizations using Microsoft Office 2016, 2019, 2021, or 2024 should prioritize patching this vulnerability to prevent local code execution by unauthorized attackers. IT administrators, security teams, and operators of affected systems should take immediate action to assess their exposure and apply necessary mitigations.

Technical summary

The CVE-2026-50301 vulnerability is a heap-based buffer overflow in Microsoft Office. It has a CVSS score of 7.8 and a CVSS vector of CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H. The vulnerability is classified under CWE-122. Affected products include Microsoft 365 Apps, Office 2016, Office 2019, Office 2021, and Office 2024, across various architectures.

Defensive priority

High priority should be given to patching CVE-2026-50301 due to its high severity and potential for local code execution.

Recommended defensive actions

  • Apply the official patch from Microsoft
  • Inventory and verify all Microsoft Office installations
  • Implement compensating controls such as monitoring and exception tracking
  • Restrict access to sensitive areas for users with limited privileges
  • Review relevant monitoring, detection, and logs for exposed assets that need extra review

Evidence notes

The CVE record was published on 2026-07-14T18:17:27.880Z and was last modified on 2026-07-16T19:43:45.920Z. The NVD entry is currently Analyzed. Evidence is limited to public sources and may not reflect the full scope or impact of the vulnerability. Defenders should verify affected systems and apply patches or mitigations as recommended by the vendor.

Official resources

AI-assisted PatchSiren debrief based on the supplied source corpus. The CVE record was published on 2026-07-14T18:17:27.880Z and has not been modified since then. The NVD entry is currently Analyzed.