- High 7.5
- Known exploited (CISA KEV)
CVE-2026-45498
Microsoft Defender Denial of Service Vulnerability
Scores
The facts
- Published
- 20 May 2026
- Last changed
- 23 July 2026
- NVD status
- Analyzed
- Severity
- High, CVSS 7.5 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- Affects
- microsoft defender antimalware platform
- Known exploited
- Yes. CISA added it to the Known Exploited Vulnerabilities catalogue on 20 May 2026.
- EPSS
- 1.3% chance of exploitation activity in the next 30 days (percentile 69).
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