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...
Vulnerability report
Cisco IOS and IOS XE Denial of Service
Cisco / Cisco IOS and IOS XE · Cisco IOS and IOS XE
Decision summary
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
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.
Exploitation evidence
Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.
CISA
Independent exploitation attestation added to the KEV Intelligence record.
Per-source evidence links for KEV attestations are available through the KEV Intelligence Pro API.
Learn about Pro API access| Source | Added |
|---|---|
| CISA First | 2022-03-03 00:00 UTC |
Detection
Make the evidence actionable in scanner, SOC, and edge-control workflows.
Raw values available in Pro and Enterprise.
No scanner integrations recorded yet.
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
CVSS v3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
EPSS
7.9%
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
AV:N/AC:L/Au:N/C:N/I:N/A:C
Timeline
Listed in the CISA Known Exploited Vulnerabilities catalog
Vulnerability disclosed publicly
Identifier reserved by the CNA
Pro API
Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.
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 }
}
Early warning alerts
Receive curator-selected alerts when exploitation activity warrants attention. Each alert includes the evidence and context needed to decide what requires attention now.