CVE-2026-123384
HIGHCVSS 8.8/10
Last modified
CVE-2026-123384 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. Heap-based buffer overflow in Microsoft Office Outlook allows an unauthorized attacker to execute code over a network..
Description
Heap-based buffer overflow in Microsoft Office Outlook allows an unauthorized attacker to execute code over a network.
Metrics
Weakness Enumeration
Affected Software
Source: CNA advisory (CVE.org). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Microsoft 365 Apps for Enterprise | >= 16.0.1, < https://aka.ms/OfficeSecurityReleases |
| Microsoft | Microsoft Office LTSC 2021 | >= 16.0.1, < 16.0.14334.21048 |
| Microsoft | Microsoft Office LTSC 2024 | >= 16.0.0, < 16.0.17932.21140 |
References
Timeline
- Published
- Last Modified
- Status
- Awaiting Analysis
Frequently Asked Questions
What is CVE-2026-123384?
Heap-based buffer overflow in Microsoft Office Outlook allows an unauthorized attacker to execute code over a network.
How severe is CVE-2026-123384?
CVE-2026-123384 has a CVSS score of 8.8/10 (HIGH severity).
How do I fix CVE-2026-123384?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
How Strix Helps
- How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
- Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
- PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
- AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.
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Are you affected by CVE-2026-123384?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST