November 14, 2026

CVE Watchtower

CVE-2026-118300Microsoft Out-of-bounds Read

NVDCVSS scored by secure@microsoft.com

Vulnerability Summary

Out-of-bounds read in Microsoft Office Excel allows an unauthorized attacker to disclose information over a network.
Severity Level
MEDIUM(6.5)
Published Date
Nov 10, 2026
Last Modified
Nov 13, 2026
Exploitation Status
No confirmed exploitation yet
EPSS Score (30-Day)
1.02%Probability
Root Weakness (CWE)
CWE-125: Out-of-bounds Read β†—
The software reads data past the end, or before the beginning, of the intended buffer.
CVSS v3.1 Base Metrics — Score 6.5 (MEDIUM)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionRequired
ScopeUnchanged
ConfidentialityHigh
IntegrityNone
AvailabilityNone

Affected & Patched Versions

Affected Versions
  • Microsoft 365 Apps
  • Microsoft Microsoft 365
  • Microsoft Office 2021
  • Microsoft Office 2024
  • Microsoft Office Online Server < 16.0.10417.20236
Patched Versions
  • Microsoft Office Online Server 16.0.10417.20236

What to do

Fix it during your normal patch cycle. No exploitation is confirmed yet.

  1. Check whether you run Microsoft and which version.
  2. Update to a patched version listed above, then confirm the new version.

Timeline

  • Nov 10, 2026Published
  • Nov 13, 2026Record last modified

Score, severity and exploitation changes are tracked from the day Watchtower started logging them.

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External References

Data last checked: Nov 14, 2026 05:11 UTC