CVE-2016-6415: in the CISA KEV catalogue

Cisco IOS, IOS XR, and IOS XE IKEv1 Information Disclosure Vulnerability. CISA added CVE-2016-6415 to the Known Exploited Vulnerabilities catalogue on 2023-05-19 with a default due date of 2023-06-09. Known ransomware campaign use: Unknown. Forensic triage flag: No.

Cisco IOS, IOS XR, and IOS XE contain insufficient condition checks in the part of the code that handles Internet Key Exchange version 1 (IKEv1) security negotiation requests. contains an information disclosure vulnerability in the Internet Key Exchange version 1 (IKEv1) that could allow an attacker to retrieve memory contents. Successful exploitation could allow the attacker to retrieve memory contents, which can lead to information disclosure. (CISA description)

Vendor / product: Cisco IOS, IOS XR, and IOS XE
CWE: CWE-200
CISA required action: Apply updates per vendor instructions.
EPSS: 88%, percentile 99 (scored 2026-11-03)

EPSS puts about 88 in 100 odds (88%) on exploitation activity being observed in the next 30 days. Its score is higher than or equal to that of 99% of scored CVEs. This is a model estimate about exploitation anywhere, not about your environment.

Vendor and reference links (from CISA)

Your own deadline under CISA BOD 26-04 depends on exposure, automatability and technical impact: work it out with the BOD 26-04 calculator.

Data dates. CISA KEV catalogue version 2026.11.03, released 2026-11-03, 1,767 entries (checked 2026-11-03). EPSS model v2026.06.15, scored 2026-11-03, 399,388 CVEs. Sources: CISA and FIRST (EPSS by FIRST; scores generated by Empirical Security). Copied to our own database and refreshed automatically; if a refresh fails, the previous copy keeps serving with its own date.

Frequently asked questions

Is CVE-2016-6415 in the CISA KEV catalogue?

Yes. CISA added CVE-2016-6415 (Cisco IOS, IOS XR, and IOS XE IKEv1 Information Disclosure Vulnerability) to the Known Exploited Vulnerabilities catalogue on 2023-05-19. CISA's default due date for it is 2023-06-09.

Is CVE-2016-6415 used in ransomware attacks?

CISA marks known ransomware campaign use as Unknown for CVE-2016-6415. That means CISA lacks confirmation, not that ransomware groups do not use it.

What should I do about CVE-2016-6415?

CISA's required action: Apply updates per vendor instructions.

Sources

CISA, Known Exploited Vulnerabilities Catalog (accessed 2026-11-03)
FIRST, Exploit Prediction Scoring System (EPSS) (EPSS by FIRST; scores generated by Empirical Security)
NVD record for CVE-2016-6415