BaselineWatch
Desk

CVE-2026-108439

8.8 high SSVC exploitation: none Analyzed

Heap-based buffer overflow in Microsoft Office Word allows an unauthorized attacker to execute code over a network.

Fix

Microsoft's update · Critical

  • Release Notes — Microsoft Office LTSC for Mac 2021, Microsoft Office LTSC for Mac 2024, Microsoft Office 365 for Mac · build 16.114.26101123
  • Release Notes — Microsoft Office LTSC 2021 for 64-bit editions, Microsoft Office LTSC 2021 for 32-bit editions · build 16.0.14334.20974
  • Release Notes — Microsoft Office LTSC 2024 for 64-bit editions, Microsoft Office LTSC 2024 for 32-bit editions · build 16.0.17932.21056
  • Release Notes — Microsoft 365 Apps for Enterprise for 64-bit Systems, Microsoft 365 Apps for Enterprise for 32-bit Systems · build https://aka.ms/OfficeSecurityReleases

From the 2026-Oct release note of Microsoft's Security Update Guide, revised 2026-10-28 · Exploitation Less Likely.

Patch, vendor advisory and mitigation references on NVD 1

Vendor advisories in the News 1

Every line above is quoted from NVD, CISA, Microsoft, the vendor's own advisory or DISA; nothing is generated.

Change history 5

  1. Cpes+9 CPE criteria (now 9)NVD modified 2026-10-20 12:27
  2. StatusPublished → AnalyzedNVD modified 2026-10-20 12:27
  3. StatusUndergoing Analysis → PublishedNVD modified 2026-10-19 19:30
  4. StatusReceived → Undergoing AnalysisNVD modified 2026-10-17 04:16
  5. First seenCVSS 8.8NVD modified 2026-10-15 21:17

Affected (CPE criteria) 9

  • cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x64:*
  • cpe:2.3:a:microsoft:365_apps:-:*:*:*:enterprise:*:x86:*
  • cpe:2.3:a:microsoft:microsoft_365:-:*:*:*:*:macos:*:*
  • cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:-:x64:*
  • cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:-:x86:*
  • cpe:2.3:a:microsoft:office_2021:-:*:*:*:ltsc:macos:-:*
  • cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:-:x64:*
  • cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:-:x86:*
  • cpe:2.3:a:microsoft:office_2024:-:*:*:*:ltsc:macos:-:*

References 1