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: 2022-03-24. 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://quickview.cloudapps.cisco.com/quickview/bug/CSCuw77959
- https://quickview.cloudapps.cisco.com/quickview/bug/CSCsm45390
- http://www.securityfocus.com/bid/101034
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20170927-dhcp
- http://www.securitytracker.com/id/1039445
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2017-12240
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": 0.13773,
"percentile": 0.96564
}10 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-10",
"epss": 0.13773,
"percentile": 0.96542
}09 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-09",
"epss": 0.13773,
"percentile": 0.96539
}08 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-08",
"epss": 0.13773,
"percentile": 0.96537
}07 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-07",
"epss": 0.13773,
"percentile": 0.96535
}07 Nov 2026, 06:20 Jerusalem · CVE Program record changed
Stored CNA snapshot at this observation.
{
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}06 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-06",
"epss": 0.13773,
"percentile": 0.9653
}05 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-05",
"epss": 0.13773,
"percentile": 0.96528
}04 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-04",
"epss": 0.13773,
"percentile": 0.96525
}03 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-03",
"epss": 0.13773,
"percentile": 0.96518
}03 Nov 2026, 02:22 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-02",
"epss": 0.13773,
"percentile": 0.96514
}03 Nov 2026, 02:22 Jerusalem · CISA KEV status changed
Stored KEV snapshot at this observation.
{
"cveID": "CVE-2017-12240",
"cwes": [
"CWE-20"
],
"dateAdded": "2022-03-03",
"dueDate": "2022-03-24",
"forensicTriage": "No",
"knownRansomwareCampaignUse": "Unknown",
"notes": "https://nvd.nist.gov/vuln/detail/CVE-2017-12240",
"product": "IOS and IOS XE Software",
"requiredAction": "Apply updates per vendor instructions.",
"shortDescription": "The Dynamic Host Configuration Protocol (DHCP) relay subsystem of Cisco IOS and Cisco IOS XE Software contains a vulnerability that could allow an unauthenticated, remote attacker to execute arbitrary code and gain full control of an affected system.",
"vendorProject": "Cisco",
"vulnerabilityName": "Cisco IOS and IOS XE Software DHCP Remote Code Execution Vulnerability"
}