Cisco IOS ↗
Cisco · Network / Security
20/100 Critical · exploited
Summary iPlain-English security verdict for Cisco IOS, generated from its current health score, actively-exploited vulnerabilities, and latest supported version.
Cisco IOS currently scores 20/100 — critical, with active exploitation. 38 of its known vulnerabilities are being actively exploited in the wild (CISA KEV), including CVE-2017-3881. Upgrade immediately and review your exposure to the actively-exploited CVEs below. Note: this product is assessed at the product level on recent (365-day) activity rather than an exact per-version match, so it is never marked a confident "healthy".
Disclosure trend iNew CVEs published for Cisco IOS each year (NVD). A higher bar means more disclosures that year — more scrutiny, not necessarily less safe.
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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-2017-3881 CRITICAL ● exploited Improper input validation EPSS 94% → see advisory CVE-2018-0171 CRITICAL ● exploited Improper input validation EPSS 93% → see advisory CVE-2016-6415 HIGH ● exploited Information disclosure EPSS 93% → fixed in 5.3.0 CVE-2017-6736 HIGH ● exploited Memory corruption EPSS 88% → see advisory CVE-2017-6737 HIGH ● exploited Memory corruption EPSS 20% → see advisory CVE-2017-6738 HIGH ● exploited Memory corruption EPSS 20% → see advisory CVE-2017-6739 HIGH ● exploited Memory corruption EPSS 20% → see advisory CVE-2017-6743 HIGH ● exploited Memory corruption EPSS 20% → see advisory CVE-2017-6740 HIGH ● exploited Memory corruption EPSS 16% → see advisory CVE-2018-0156 HIGH ● exploited CWE-399 EPSS 16% → see advisory CVE-2017-6742 HIGH ● exploited Memory corruption EPSS 15% → see advisory CVE-2018-0158 HIGH ● exploited Improper input validation EPSS 15% → see advisoryℹ product-level posture (last 365d); exact per-version verdict pending precise version mapping