Vulnerability · Published Jul 14, 2026 · Assigned by microsoft
CVE-2026-55011Microsoft Defender Remote Code Execution Vulnerability
High 7.8
In plain English
A high-severity security flaw in Microsoft Malware Protection Engine from Microsoft. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 41% of all known vulnerabilities).
Severity (CVSS 3.1)7.8High
Exploit odds (30 days)0.5%top 59.4% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Integer underflow (wrap or wraparound) in Microsoft Defender allows an unauthorized attacker to execute code locally.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Microsoft | Microsoft Malware Protection Engine | 1.1.0.0 – before 1.1.26060.3008 |
Weakness: CWE-191 · Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C
References
- Microsoft Defender Remote Code Execution Vulnerability vendor-advisory, patch