Threats / Cisco / CVE-2018-0171
CVE-2018-0171
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-06-22
Cisco IOS and XE vulnerability
Cisco IOS and IOS XE fail to properly validate packet data, allowing unauthenticated remote attackers to cause denial of service, device reload, or execute code.
Verdict
Today item — known-exploited.
An unauthenticated remote attacker can send malformed packets to trigger device reload, denial of service, or achieve remote code execution on affected Cisco routing and switching infrastructure without authentication.
01
Is it exploitable?
— the evidence, ranked above the scoreExploit available
Fully weaponized — public exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
29 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 2021-11-03).
Probability (EPSS)
EPSS 0.9951 — 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. Confirm exact fixed builds in the vendor advisory.
Weakness (CWE)
Mapped to CWE-20 Improper Input Validation.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution 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 board1
Front door — unauthenticated access narrative 1
Attacker
I craft and send malformed packets to a vulnerable Cisco device on the network.
Business
Network infrastructure becomes unstable as devices reload unexpectedly, disrupting routing and connectivity.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I exploit the packet validation flaw to trigger a denial-of-service condition on the target device.
Business
Critical network services become unavailable, impacting business operations and customer access.
3
Lateral reach — past segmentation narrative 3
Attacker
I leverage the vulnerability to execute arbitrary code on the affected device with no authentication required.
Business
Attackers gain control of network infrastructure, enabling data theft, lateral movement, and persistent compromise of the organization's network.
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.
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