Exploitation evidence
Known exploited · CISA KEV listed
Added 2022-03-03. Ransomware campaign use: Unknown.
CISA required action: Apply updates per vendor instructions.
CISA due date: 2022-03-17. This is the catalog’s deadline, not an assessment of your organization’s exposure.
KEV checked 13 Nov 2026, 00:20 Jerusalem · Original catalog ↗Reported products and versions
n/a / Cisco IOS and IOS XE
Default status: Not specified
- affected: Cisco IOS and IOS XE
Fixes and workarounds
No explicit solution text in the downloaded CVE record. Consult the vendor advisory; unaffected version ranges are shown above as reported, not inferred as a patch recommendation.
Sources and related reporting
CVE Program record ↗ · Download tracked evidence as JSON
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20180328-dhcpr2
- http://www.securityfocus.com/bid/103545
- https://ics-cert.us-cert.gov/advisories/ICSA-18-107-04
- https://www.tenable.com/security/research/tra-2018-06
- http://www.securitytracker.com/id/1040591
- https://ics-cert.us-cert.gov/advisories/ICSA-18-107-05
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2018-0173
Observed change timeline
History begins when Egret first downloads each source. It is not the complete upstream CVE history.
12 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-12",
"epss": 0.07608,
"percentile": 0.94633
}10 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-10",
"epss": 0.07608,
"percentile": 0.94599
}09 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-09",
"epss": 0.07608,
"percentile": 0.94592
}08 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-08",
"epss": 0.07608,
"percentile": 0.9459
}07 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-07",
"epss": 0.07608,
"percentile": 0.94585
}07 Nov 2026, 00:20 Jerusalem · CVE Program record changed
Stored CNA snapshot at this observation.
{
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"dateReserved": "2017-11-27T00:00:00.000Z",
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}06 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-06",
"epss": 0.07608,
"percentile": 0.94577
}05 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-05",
"epss": 0.07608,
"percentile": 0.94573
}04 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-04",
"epss": 0.07608,
"percentile": 0.94568
}03 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-03",
"epss": 0.07608,
"percentile": 0.94558
}03 Nov 2026, 02:22 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-02",
"epss": 0.07608,
"percentile": 0.94552
}03 Nov 2026, 02:22 Jerusalem · CISA KEV status changed
Stored KEV snapshot at this observation.
{
"cveID": "CVE-2018-0173",
"cwes": [
"CWE-20"
],
"dateAdded": "2022-03-03",
"dueDate": "2022-03-17",
"forensicTriage": "No",
"knownRansomwareCampaignUse": "Unknown",
"notes": "https://nvd.nist.gov/vuln/detail/CVE-2018-0173",
"product": "IOS and IOS XE Software",
"requiredAction": "Apply updates per vendor instructions.",
"shortDescription": "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 can allow for denial-of-service (DoS).",
"vendorProject": "Cisco",
"vulnerabilityName": "Cisco IOS and IOS XE Software Improper Input Validation Vulnerability"
}