CVE-2018-0173

Read full description

A vulnerability in the Cisco IOS Software and Cisco IOS XE Software function that restores encapsulated option 82 information in DHCP Version 4 (DHCPv4) packets could allow an unauthenticated, remote attacker to cause an affected device to reload, resulting in a Relay Reply denial of service (DoS) condition. The vulnerability exists because the affected software performs incomplete input validation of encapsulated option 82 information that it receives in DHCPOFFER messages from DHCPv4 servers. An attacker could exploit this vulnerability by sending a crafted DHCPv4 packet to an affected device, which the device would then forward to a DHCPv4 server. When the affected software processes the option 82 information that is encapsulated in the response from the server, an error could occur. A successful exploit could allow the attacker to cause the affected device to reload, resulting in a DoS condition. Cisco Bug IDs: CSCvg62754.

CVSS 8.6 (HIGH) KEV: KNOWN CATALOG

Attention and evidence

HYPE SCORE

0.0/10

REALITY · THREAT PRIORITY

8.3/10

General review priority; not probability

Evidence confidence: Exploitation recorded

Why this priority?

Recorded exploitation baseline: +7.00
Technical severity: CVSS 8.6: +1.29
Fresh EPSS: 7.61%: +0.04

General review priority, not probability, victim count or asset-specific risk. A range covers missing CVSS/EPSS inputs within the current evidence state.

Sources: 1 documents and public datasets.

Hype components

Headline sample (25%)

0/100

Press, 30 days (60%)

0/100

Grounded branding (15%)

0/100

HYPE TOTAL0/100

Sources and documents

Security Affairs

Press · 19 Apr 2018, 07:00 · Rockwell Automation Allen-Bradley Stratix and ArmorStratix switches are exposed to hack due to Cisco IOS flaws - Security Affairs

Score evolution

● Hype ● Reality

Earlier evidence-support scores are retained in history; this chart shows only the current priority definition.

First record: hype 0.0 · reality 8.3 (2026-11-02 15:12). The curve appears once the score changes.

Public exploit evidence

Public exploit entries / repo candidates

Evidence context and dated references

Reality is general threat/review priority, combining observed exploitation, CVSS severity and fresh EPSS. Evidence confidence is separate. This is not calibrated risk, a victim count or an asset-specific assessment. A range reflects missing numeric inputs.

Evidence in context

Confidence in exploitation evidence: Exploitation recorded
Priority basis: Recorded exploitation; CVSS 8.6; EPSS 7.6%
Attention, last 30 days: 0 distinct story titles; 0 press documents; 0 publisher domains.
Technical potential: network access, no prior privileges, no user interaction.
Observed activity: Exploitation recorded in CISA KEV.
Known scale: Not quantified.
Evidence confidence basis: Trusted exploitation confirmation

Score evaluated: 2026-11-05 13:57:54.561888+00:00 · EPSS snapshot: 2026-11-05T12:03:04Z

Source event timeline

Published

28 Mar 2018, 22:00

First press mention

19 Apr 2018, 07:00

Latest press mention

19 Apr 2018, 07:00

Added to the CISA KEV catalog

03 Mar 2022, 00:00

Score calculated

05 Nov 2026, 13:57