VulnTideExploited vulnerabilities, by vendor. Data as of 28 Oct 2026.
Known exploitedIn CISA's KEV catalog since 19 May 2023Ransomware use: unknown
Cisco IOS, IOS XR, and IOS XE

CVE-2016-6415: Cisco IOS, IOS XR, and IOS XE IKEv1 Information Disclosure Vulnerability

Is it exploited?

Yes. CISA added it to the Known Exploited Vulnerabilities catalog on 19 May 2023, 2,433 days after the CVE record was published.

How likely is exploitation in the next 30 days?
87.7%

EPSS score, percentile 99.8 of all scored records

How severe?
7.5 High

CVSS v3.1 base score, from CISA's enrichment of the record

What should I do?

CISA deadline 9 Jun 2023. Apply updates per vendor instructions.

Advisories and patches (1)

Which versions are affected?

Not stated. The CVE record gives vendor and product as “n/a” and the version as “unspecified”.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

What to do

Required action, set by CISA

Apply updates per vendor instructions.

CISA due date for this action: 9 June 2023.

Advisories and patches

Linked from CISA's catalog entry

Affected products and versions

The CVE record does not name affected products or versions: vendor and product are “n/a” and the version is “unspecified”.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

About this vulnerability

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.

Summary: CISA's KEV catalog, as of 28 Oct 2026.

  • CISA added CVE-2016-6415 to its Known Exploited Vulnerabilities (KEV) catalog on 19 May 2023.
  • CISA's ransomware flag for this entry is "Unknown": no evidence of ransomware use in the catalog, which is not proof of none.
  • The due date CISA sets for the required action is 9 Jun 2023.
  • The CVE record was published on 19 Sep 2016, 2,433 days before it was added to KEV.
  • The CVE record carries a CVSS v3.1 base score of 7.5 (High), taken from CISA's enrichment of the record.
  • FIRST's EPSS model puts the probability of exploitation in the next 30 days at 87.7% (percentile 99.8), as of 28 Oct 2026.
  • CISA's SSVC assessment in the CVE record: exploitation active, automatable yes, technical impact partial.

Source: CISA Known Exploited Vulnerabilities (KEV) catalog, 2026.10.28, as of 28 Oct 2026; CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026; FIRST Exploit Prediction Scoring System (EPSS), v2026.06.15, as of 28 Oct 2026. About the data.

Description

The server IKEv1 implementation in Cisco IOS 12.2 through 12.4 and 15.0 through 15.6, IOS XE through 3.18S, IOS XR 4.3.x and 5.0.x through 5.2.x, and PIX before 7.0 allows remote attackers to obtain sensitive information from device memory via a Security Association (SA) negotiation request, aka Bug IDs CSCvb29204 and CSCvb36055 or BENIGNCERTAIN.

Source: CVE List V5 (CVE Program), cve_2026-10-28_0000Z, as of 28 Oct 2026. About the data.

Weakness

  • CWE-200: Exposure of Sensitive Information to an Unauthorized Actor

CWE and CAPEC are maintained by MITRE; the entries are those named in the CVE record and the KEV entry.

Timeline

DateEvent
19 Sep 2016CVE record published
19 May 2023Added to CISA KEV
9 Jun 2023CISA due date for the required action
12 Jan 2026CVE record last updated

References

  • 1036841 (Vulnerability database)
  • 93003 (Vulnerability database)

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