CVE-2026-26134
7.8 · HIGHOverview
CVE-2026-26134 is a high-severity vulnerability affecting microsoft 365_copilot. It was published on March 10, 2026 and has a CVSS 3.1 base score of 7.8 (HIGH).
This vulnerability has a CVSS 3.1 base score of 7.8, rated HIGH. It requires local or adjacent network access to exploit. Some level of privileges is required for exploitation.
Technical Description
Integer overflow or wraparound in Microsoft Office allows an authorized attacker to elevate privileges locally.
Remediation
Check the references section for vendor advisories and patches from microsoft. Update 365_copilot to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| microsoft | 365_copilot | >= 0, < 16.0.19822.20000 | Affected |
Frequently Asked Questions
What is CVE-2026-26134?
CVE-2026-26134 is a high-severity vulnerability affecting microsoft 365_copilot. It was published on March 10, 2026 and has a CVSS 3.1 base score of 7.8 (HIGH).
How severe is CVE-2026-26134?
This vulnerability has a CVSS 3.1 base score of 7.8, rated HIGH. It requires local or adjacent network access to exploit. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2026-26134?
Check the references section for vendor advisories and patches from microsoft. Update 365_copilot to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-26134?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-26134 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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