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Threats / Cisco / CVE-2017-12237
CVE-2017-12237 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Cisco IOS and XE Software vulnerability

A vulnerability in the IKEv2 module of Cisco IOS and IOS XE allows unauthenticated remote attackers to cause denial of service through high CPU utilization, traceback messages, or device reload.

Verdict

Today item — known-exploited.

An unauthenticated remote attacker can trigger resource exhaustion in affected Cisco IOS and IOS XE devices via crafted IKEv2 traffic, resulting in service disruption. The vulnerability has been exploited in the wild.

CISA KEV Yes · 2022-03-033EPSS 0.06938 (verify live)4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
2 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-03-03).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.06938 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Cisco, IOS and IOS XE Software. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-399 Resource Management Errors — weakness family: Resource / availability.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-399 · Resource Management ErrorsResource / availability
02

Who’s exploiting it?

— attribution turns risk into urgency
Attribution not established

No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.

03

Why it matters

— the attack path, told twice: adversary, then board
1

Front door — unauthenticated access narrative 1

Attacker
I send specially crafted IKEv2 packets to the target device without authentication.
Business
Network availability is compromised as the device becomes unresponsive or reloads.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I trigger excessive CPU consumption on the IKEv2 processing module through repeated malicious requests.
Business
Critical network infrastructure experiences performance degradation or complete outage.
3

Lateral reach — past segmentation narrative 3

Attacker
I cause the device to generate traceback messages and potentially reload, disrupting VPN and security services.
Business
Remote access and encrypted communications fail, impacting business continuity and security posture.
04

What to do

— defensible action
  • Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05

Coverage & confidence

— what we know, and what we don’t

Established (cited)

  • KEV listing (CISA)
  • EPSS probability (FIRST)
  • 2 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Catalogued by cisco (CNA)
  • Coverage gaps — stated, not hidden

  • No EUVD / GCVE mirror in feed — single-authority dependency for the identifier.
  • EPSS & exposure are time-varying; verify live at the source.
  • Threat-actor attribution not established from feed data — absence of a name is not absence of compromise.
  • No finder/reporter credit recorded in the public CVE entry — the work behind this find is unattributed.
  • Disclosure & credit2
    Catalogued by ciscoCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.