Advisories
Microsoft Excel Information Disclosure CVE-2026-81400: Patch Office for Mac
Microsoft released Office for Mac security updates for CVE-2026-81400, an information disclosure vulnerability in Microsoft Excel. Affected Mac Office installations should be patched; other Microsoft Office products are not listed as requiring action. Defenders should inventory Mac endpoints and verify the applicable update is deployed.
What happened
Microsoft released security updates for Microsoft Office for Mac to address CVE-2026-81400, an information disclosure vulnerability in Microsoft Excel. The advisory says the issue affects Mac-based Office software and that other Microsoft Office products do not require action.
Impact
Defenders should treat this as a potential data-exposure issue for Mac endpoints running affected Excel components. The source does not provide affected versions, exploitability, or severity, so scope should be confirmed against Microsoft release notes and internal patch inventory.
What to do
- Identify Mac systems running Microsoft Office and Excel, especially unmanaged or delayed-patch hosts.
- Apply the applicable Microsoft Office for Mac update from Microsoft release notes.
- Verify patch status after deployment and document any systems that cannot be updated immediately.
- Review recent Excel file handling and shared-folder or email-borne document activity if the environment has high exposure to untrusted Office files.
For this CVE, Microsoft's stated guidance is to install the Office for Mac update for the affected product; no action is required for other Microsoft Office software.
Related vulnerabilities
Microsoft issues Office for Mac update for Excel information disclosure CVE-2026-81393
Microsoft released a security update for Microsoft Office for Mac to address CVE-2026-81393, an information disclosure vulnerability in Microsoft Excel. The advisory directs customers running affected Mac Office products to install the update, while other Microsoft Office software is not called out for action. Defenders should prioritize Mac endpoint patching and verify deployment.
Read briefing
Microsoft Office for Mac Update Fixes CVE‑2026‑97779 Information Disclosure
Microsoft released a patch for Office for Mac that mitigates CVE‑2026‑97779, an information‑disclosure flaw. Only Mac users of Office are affected; other Office platforms do not require action. Install the update immediately to prevent data leakage.
Read briefing
Microsoft Office for Mac Excel Information Disclosure CVE-2026-88184 – Immediate Update Required
Microsoft released a patch for an information‑disclosure flaw in Excel on Mac (CVE‑2026‑88184). Mac users of Office must install the update to prevent data leakage. Other Office platforms are unaffected.
Read briefing
Microsoft Office for Mac Vulnerability CVE-2026-80082 – Information Disclosure
Microsoft Office for Mac is affected by CVE-2026-80082, an information‑disclosure flaw that can expose user data. The issue is fixed in the latest Office update; administrators should deploy the patch immediately. Non‑Mac Office users are not impacted.
Read briefing