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CVE-2018-0159

Cisco IOS and XE Software Internet Key Exchange Version 1 Denial-of-Service

7.5 HIGHActively exploited (CISA KEV)EPSS 6.87%
  1. Published28 Mar 2018
  2. Added to CISA KEV3 Mar 2022
  3. Remediation due17 Mar 2022
Actively exploited (CISA KEV)

A vulnerability in the implementation of Internet Key Exchange Version 1 (IKEv1) functionality in Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial-of-service (DoS) condition.

Added to KEV: 3 Mar 2022Federal remediation due: 17 Mar 2022

Description

A vulnerability in the implementation of Internet Key Exchange Version 1 (IKEv1) functionality in Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a denial of service (DoS) condition. The vulnerability is due to improper validation of specific IKEv1 packets. An attacker could exploit this vulnerability by sending crafted IKEv1 packets to an affected device during an IKE negotiation. A successful exploit could allow the attacker to cause an affected device to reload, resulting in a DoS condition. Cisco Bug IDs: CSCuj73916.

CVSS 3.1 breakdown

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
ScopeUnchanged
ConfidentialityNone
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

Cisco iOS15.3\(3\)s
Cisco iOS XE15.3\(3\)s

Remediation

No fixed version is recorded in the NVD data. Check the vendor advisory for the latest guidance.

References

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Frequently asked

Is CVE-2018-0159 being actively exploited?

Yes. CVE-2018-0159 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added 3 Mar 2022.

How severe is CVE-2018-0159?

CVE-2018-0159 has a CVSS 3.1 base score of 7.5, rated high. EPSS estimates a 6.87% probability of exploitation.

Which products are affected by CVE-2018-0159?

Affected products include Cisco iOS, Cisco iOS XE.

How do I fix CVE-2018-0159?

Apply the vendor's patch or advisory guidance, then verify no affected versions remain across your devices.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2018-0159 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. Because it is on the CISA KEV list, Secuno flags any affected asset as top-priority automatically. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.