4.0
Medium
CVE-2026-45498 Microsoft Defender Denial of Service Vulnerability
Active exploitation observed
· CISA KEV catalogue
Required action
Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Ransomware campaigns
Not observed so far
Description
Microsoft Defender Denial of Service Vulnerability
Affected products and versions
| Product | Affected versions | Fixed in |
|---|---|---|
| Microsoft Defender Antimalware Platform 4.0 | 4.0.0.0 → < 4.18.26040.7 | 4.18.26040.7 |