Vulnerability Intelligence Report
Microsoft Defender Remote Code Execution Vulnerability
CVE-2026-55011
Integer underflow (wrap or wraparound) in Microsoft Defender allows an unauthorized attacker to execute code locally.
No Active Exploit Signals
CVSS Base Score
7.8
HIGH
Exploitability:1.9
Impact Score:5.9
EPSS Probability:0.47%
Executive Threat Verdict
Evaluating...
Evaluating Threat Landscape...
Assessing known weaponization, exploitation telemetry, and federal advisories.
Attack Surface
—
Authentication
—
Weaponization
—
SSVC Action
—
Weaknesses (CWE)
CWE-191 ↗CWE-191: Integer Underflow (Wrap or Wraparound)
Affected Products & Versions
| Vendor | Product | Affected Versions |
|---|---|---|
| Microsoft | Microsoft Malware Protection Engine | 1.1.0.0 < 1.1.26060.3008 (affected) |
References & Technical Advisories
No reference links found.
Threat Intelligence Signals
EPSS Score
0.466%
GitHub Advisory
Identity & Timeline
| Status | PUBLISHED |
| Assigning Authority | Microsoft Corporation · Vendor · USA |
| Reserved | 2026-06-16T14:12:44 |
| Published | 2026-07-14T17:05:03 |
| Patch Date | 2026-07-14 |
| Last Updated | 2026-09-25T18:20:21 |
Community Chatter & Buzz