Exploited CVEs / Cisco / CVE-2016-6415
CVE-2016-6415
Cisco IOS, IOS XR, and IOS XE IKEv1 Information Disclosure Vulnerability. Exploitation in the wild is confirmed by CISA, not predicted. Federal agencies were required to remediate by 2023-06-09 (that deadline has passed); treat that date as the outer bound for your own environment. The fix is in the vendor advisory: Cisco Security Advisories (PSIRT), linked below.
Actively exploited Cisco IOS, IOS XR, and IOS XE vulnerability, High severity, CVSS 7.5. Added to the CISA KEV catalog 2023-05-19.
Risk summary
Updated July 27, 2026. Data refreshed on every build from MSRC, CISA KEV, and FIRST EPSS.
Senserva AI Opinion for CVE-2016-6415
Cisco IOS, IOS XR, and IOS XE leak information through insufficient condition checks in IKEv1 security negotiation, a flaw tied to the leaked exploit tooling era and confirmed exploited (KEV 2023-05-19). It rates Severity High (CVSS 7.5) with an 88% EPSS score. Devices terminating legacy IKEv1 VPNs expose this to anyone who can send them IKE packets, which usually means the whole internet.
Do this: Identify devices still accepting IKEv1 negotiations, patch them, and migrate remaining tunnels to IKEv2.
AI-generated from public data, 2026-07-07. Verify against the vendor advisory before acting.
Senserva AI Opinion and rich prompt for CVE-2016-6415
Copy this prompt into Claude, ChatGPT, or Copilot. The facts are included, sourced from this page.
Full tracking and change history for CVE-2016-6415
Published and last-revised dates are authoritative, from Microsoft MSRC (or the CISA KEV date-added). Senserva additionally records day-to-day changes from 2026-07-07, refreshed several times a day; the change count reflects that forward-only tracking.
CISA required action
Federal (BOD 22-01) remediation due date: 2023-06-09 (past due).
Apply updates per vendor instructions.
Official fix for CVE-2016-6415
The authoritative fix and affected-version list are published by the vendor. Find the IOS, IOS XR, and IOS XE advisory on Cisco Security Advisories (PSIRT).
Common questions about CVE-2016-6415
Is CVE-2016-6415 actively exploited?
Yes. CVE-2016-6415 was added to the CISA Known Exploited Vulnerabilities (KEV) catalog on 2023-05-19, which means exploitation in the wild has been confirmed, not predicted. Its EPSS 30-day exploitation probability is 87%.
What is the CISA deadline and required action for CVE-2016-6415?
CISA set the federal (BOD 22-01) remediation due date at 2023-06-09, which has passed; treat any unremediated system as overdue. The verbatim required action: Apply updates per vendor instructions.
What fixes CVE-2016-6415?
The authoritative fix is in the vendor advisory: see Cisco Security Advisories (PSIRT) for the patched IOS, IOS XR, and IOS XE versions and any workarounds. KEV listing makes this a fix-first item: patch it ahead of higher-CVSS issues nobody is exploiting.
Can I ask my own AI about CVE-2016-6415?
Yes. This page includes a free, ready-to-paste AI prompt containing CVE-2016-6415's key facts: severity, CVSS, EPSS, the KEV date, the CISA due date, and the required action. Copy it into Claude, ChatGPT, or Copilot; the data is refreshed twice a day (5 AM and 3 PM US Central).
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Authoritative references
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