CVE-2026-45498CISA KEV

Microsoft Defender Denial of Service Vulnerability

Severity unknownCVSS unknownCheck the vendor advisory for fixed versions

CISA lists this Microsoft vulnerability as known exploited. Its MSRC release detail is outside this installation's collected history.

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CISA catalog record

Microsoft Defender contains an unspecified vulnerability that allows for denial of service.

Product: Defender
Added to KEV: 20 May 2026
Federal remediation due: 3 Jun 2026
Known ransomware use: Not reported

Page history

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Field-level log (2)

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23 Oct 2026 · 09:33:49 UTC Source coverage: cisa-kevIncomplete → Current
23 Oct 2026 · 08:31:50 UTC Source coverage: cisa-kevCurrent → Incomplete

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Exploitation and risk

Source status

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CVE-2026-45498

Listed in CISA KEV · added 20 May 2026 · Microsoft · Defender

Microsoft Defender contains an unspecified vulnerability that allows for denial of service.

CISA source

No EPSS score is available here for this CVE.

Saved 23 Oct 2026 16:01:26 UTC · View this risk record (JSON)

cve-program · CVE-2026-45498

Published

Microsoft Defender Denial of Service Vulnerability

Source published: 20 May 2026 13:09:12 UTC
Source modified: 10 Aug 2026 15:13:18 UTC
Saved here: 23 Oct 2026 15:48:27 UTC
Source terms: CVE Program Terms of Use

Original source record · Cite this exact observation · Complete original publisher JSON

Source: cve-program · CVE Program Terms of Use. The publisher's wording is preserved. ChangeIntel groups the information and labels changes. The JSON record includes additional source fields.

CVSS 3.1 · 4.0 CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:U/RL:O/RC:C