CVE-2026-123383: Microsoft Office Outlook Remote Code Execution Vulnerability
Published Nov 10, 2026
·Updated
Heap-based buffer overflow in Microsoft Office Outlook allows an unauthorized attacker to execute code over a network.
Other sources
Microsoft Office Outlook Remote Code Execution Vulnerability
— Microsoft
Affected Software
4 affected componentsFixes available
Microsoft Office LTSC 2021<16.0.14334.21048
16.0.14334.21048
Microsoft Office LTSC 2024<16.0.17932.21140
16.0.17932.21140
Microsoft Office LTSC 2021<16.0.14334.21048
16.0.14334.21048
Microsoft Office LTSC 2024<16.0.17932.21140
16.0.17932.21140
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 16.0.14334.21048 - Upgrade
Upgrade to a fixed release to a version that resolves this vulnerability.
Fixed in 16.0.17932.21140
Event History
Nov 10, 2026
CVE Published
via Microsoft·04:00 PM
Data Sourced
via Microsoft·04:00 PM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·04:00 PM
Affected Software
CVE Published
via MITRE·06:22 PM
Data Sourced
via MITRE·06:22 PM
DescriptionSeverity
Data Sourced
via NVD·07:20 PM
DescriptionSeverityWeakness