Cisco IOS XE Wireless Controller Software for the Catalyst 9000 Family SNMP Trap Denial of Service Vulnerability

published 2020-09-24 6y ago modified 2026-06-17 4mo ago also EUVD-2020-24661

cvss: 7.4; version 3.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.6%; EPSS 0.6% chance of exploitation in 30 days, percentile 50%
public exploits: 0; none known

A vulnerability in Simple Network Management Protocol (SNMP) trap generation for wireless clients of the Cisco IOS XE Wireless Controller Software for the Cisco Catalyst 9000 Family could allow an unauthenticated, adjacent attacker to cause the device to unexpectedly reload, causing a denial of service (DoS) condition on an affected device. The vulnerability is due to the lack of input validation of the information used to generate an SNMP trap in relation to a wireless client connection. An attacker could exploit this vulnerability by sending an 802.1x packet with crafted parameters during the wireless authentication setup phase of a connection. A successful exploit could allow the attacker to cause the device to reload, causing a DoS condition.

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CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: last yr. (2024-11-13)

Exploit prediction

0.64% chance of exploitation in the next 30 days, higher than 50% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.0	7.4	CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
NVD	3.1	7.4	CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
NVD	2.0	5.7	AV:A/AC:M/Au:N/C:N/I:N/A:C

Affected products

Cisco Cisco IOS XE Software

Classification

Weakness

CWE-20 Improper Input Validation

Technology feeds

Cisco IOS rss critical rss

References

tools.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxe-ewlc-snmp-dos-wNkedg9K
vendor-advisory

Sources

CVE List CVE-2020-3390
NVD CVE-2020-3390

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