CVEs / CVE-2016-6415

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

Known exploited in the CISA KEV catalog since 19 May 2023
high 7.5 CVSS 3.1 (NVD)
EPSS 87.6% chance of exploitation in the next 30 days, higher than 99% of CVEs (30 Oct 2026)
Last changed at its sources 17 Jun 2026

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Summary

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, Known Exploited Vulnerabilities catalog

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.
The CVE record, via NVD · published 19 Sep 2016 · NVD status: Analyzed

Affected and fixed versions

As stated by the CVE record (from the CNA)
Product	Affected	Fixed in
n/a n/a	n/a	—

Exploitation

In CISA KEV since	19 May 2023
Due date for US federal agencies	9 Jun 2023
Used in ransomware campaigns	Unknown
Required action	Apply updates per vendor instructions.

Severity

CVSS 3.1	7.5 high `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N` Scored by NVD
Weakness	CWE-200

References

CVE-2016-6415 on NVD
CVE-2016-6415 in the CISA KEV catalog
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160916-ikev1 (cited by CISA)
http://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20160916-ikev1 Vendor Advisory
http://www.securityfocus.com/bid/93003 Third Party Advisory, VDB Entry
http://www.securitytracker.com/id/1036841 Third Party Advisory, VDB Entry
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2016-6415 US Government Resource

Sources

Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.

This product uses data from the NVD API but is not endorsed or certified by the NVD.