Vulnerability Intelligence Report
Microsoft M365 Copilot Remote Code Execution Vulnerability
CVE-2026-50517
Deserialization of untrusted data in M365 Copilot allows an authorized attacker to execute code over a network.
Deserialization
No Active Exploit Signals
CVSS Base Score
9.9
CRITICAL
Exploitability:3.2
Impact Score:6.1
EPSS Probability:1.69%
Executive Threat Verdict
Evaluating...
Evaluating Threat Landscape...
Assessing known weaponization, exploitation telemetry, and federal advisories.
Attack Surface
—
Authentication
—
Weaponization
—
SSVC Action
—
Weaknesses (CWE)
CWE-502 ↗CWE-502: Deserialization of Untrusted Data
Affected Products & Versions
| Vendor | Product | Affected Versions |
|---|---|---|
| Microsoft | Microsoft 365 Copilot | - (affected) |
References & Technical Advisories
No reference links found.
Threat Intelligence Signals
Identity & Timeline
| Status | PUBLISHED |
| Assigning Authority | Microsoft Corporation · Vendor · USA |
| Reserved | 2026-06-04T19:00:41 |
| Published | 2026-07-24T00:01:11 |
| Patch Date | 2026-07-23 |
| Last Updated | 2026-09-25T18:25:38 |
Community Chatter & Buzz