Vulnerability report

Exploited in the wild Confirmed confidence In CISA KEV

CVE-2018-0172

Cisco IOS and IOS XE Denial of Service

Cisco / Cisco IOS and IOS XE · Cisco IOS and IOS XE

Severity
CVSS 8.6 · High
Confidence
Confirmed
Exploit status
Exploited in the wild
EPSS
7.9%
First observed
Last observed

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2018-0172 is an unauthenticated vulnerability affecting Cisco Cisco IOS and IOS XE. A vulnerability in the DHCP option 82 encapsulation functionality of Cisco IOS Software and Cisco IOS XE Software could allow an...

Is it exploited?

Yes. KEV Intelligence tracks this CVE as a known exploited vulnerability. Confidence is confirmed.

Who is affected?

Cisco / Cisco IOS and IOS XE cisco ios and ios xe.

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

Cisco IOS and IOS XE Denial of Service

A vulnerability in the DHCP option 82 encapsulation functionality of 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 exists because the affected software performs incomplete input validation of option 82 information that it receives in DHCP Version 4 (DHCPv4) packets from DHCP relay agents. An attacker could exploit this vulnerability by sending a crafted DHCPv4 packet to an affected device.

A successful exploit could allow the attacker to cause a heap overflow condition on the affected device, which will cause the device to reload and result in a DoS condition. Cisco Bug IDs: CSCvg62730.

Vendor Product Affected Status
n/a Cisco IOS and IOS XE Cisco IOS and IOS XE Affected
Published
28 Mar 2018
Exploitation Reported
03 Mar 2022
Attack vector
Remote
Complexity
Low
Privileges
None
User interaction
None

Tags

edge ios cisa

CVE References

Exploitation evidence

Why KEV Intelligence marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

CISA

Recorded 03 Mar 2022

Independent exploitation attestation added to the KEV Intelligence record.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the KEV Intelligence Pro API.

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Source Added
CISA First 2022-03-03 00:00 UTC

Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
0
User-Agents
0

Raw values available in Pro and Enterprise.

Scanner coverage

No scanner integrations recorded yet.

Virtual patch status

No KEV Intelligence virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

No detection artifacts or sensor request patterns are available for this CVE yet.

Check back as sensor telemetry and scanner integrations are updated.

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

8.6 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

EPSS

7.9%

All CVSS Scores

CVSS v3.1 8.6 High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

CVSS v2.0 7.8 High

AV:N/AC:L/Au:N/C:N/I:N/A:C

Timeline

From disclosure to observed exploitation

  1. Added to CISA KEV

    Listed in the CISA Known Exploited Vulnerabilities catalog

  2. CVE published

    Vulnerability disclosed publicly

  3. CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2018-0172

Free JSON includes basic KEV fields
{
  "cve_id": "CVE-2018-0172",
  "confidence": "Confirmed",
  "cvss_score": 8.6,
  "cvss_estimated": false,
  "epss_score": 0.07871,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}

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