Defender
Summary iPlain-English security verdict for Defender, generated from its current health score, actively-exploited vulnerabilities, and latest supported version.
Defender currently scores 20/100 — critical, with active exploitation. 2 of its known vulnerabilities are being actively exploited in the wild (CISA KEV), including CVE-2017-8540. Upgrade immediately and review your exposure to the actively-exploited CVEs below.
Disclosure trend iNew CVEs published for Defender each year (NVD). A higher bar means more disclosures that year — more scrutiny, not necessarily less safe.
Patch priority — what to act on iThe issues to fix first — actively exploited (CISA KEV) first, then by exploitation probability (EPSS), then severity. Each row's "→ fixed in" is the earliest version that patches it; "see advisory" means no fixed version is published.
Most urgent first — actively exploited, then likeliest to be exploited.
CVE-2017-8540 HIGH exploited Out-of-bounds write EPSS 72% → see advisory CVE-2021-1647 HIGH exploited EPSS 40% → see advisory CVE-2017-0290 HIGH Memory corruption EPSS 77% → see advisory CVE-2018-0986 HIGH Out-of-bounds write EPSS 61% → see advisory CVE-2017-8538 HIGH Memory corruption EPSS 50% → see advisory CVE-2017-8541 HIGH Memory corruption EPSS 50% → see advisory CVE-2017-8558 HIGH Memory corruption EPSS 44% → see advisory CVE-2006-5270 HIGH EPSS 30% → see advisoryGet alerted about Defender
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Frequently asked
Is Defender safe and patched?
Defender currently scores 20/100 — critical, with active exploitation. 2 of its known vulnerabilities are being actively exploited in the wild (CISA KEV), including CVE-2017-8540. Upgrade immediately and review your exposure to the actively-exploited CVEs below.
What should I do about Defender now?
Review the patch-priority list, apply the available fixes (or move to the latest release), and confirm against Microsoft's official advisory. Some issues are under active exploitation, so treat this as urgent.
Why is Defender listed on IsItPatched?
Defender was added automatically because CISA's Known Exploited Vulnerabilities (KEV) catalog flagged it as actively exploited in the wild. IsItPatched tracks its known CVEs, severity (CVSS), exploitation probability (EPSS) and KEV status from public data; its version and lifecycle mapping is verified over time.
lifecycle unknown — needs latest supported version
Latest security news for Defender BETA
Attributed third-party reporting linked to Defender — newest first. We surface and link the source; we don’t assert our own findings. About Emerging →
More across all tracked software on the Emerging feed →
Informational only, from public data (NVD · CISA KEV · EPSS · endoflife.date), and can lag or miss vendor-specific fixes. Always confirm against Microsoft's official advisory before you patch or upgrade.