CVE-2020-3359
highpriority · track · 35EPSS 0.015 · 74 %ileEURUUSEPSS · scored 2026-10-27
A vulnerability in the multicast DNS (mDNS) feature of Cisco IOS XE Software for Cisco Catalyst 9800 Series Wireless Controllers could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to improper validation of mDNS packets. An attacker could exploit this vulnerability by sending a crafted mDNS packet to an affected device. A successful exploit could cause a device to reload, resulting in a DoS condition.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- Fixed16.11.1cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.11.1acisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.11.1bcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.11.1ccisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.11.1scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.11.2cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.12.1cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.12.1acisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.12.1ccisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.12.1scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.12.1tcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed17.11.99SWcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (17)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-mdns-dos-3tH6cA9JCisco IOS XE Software for Catalyst 9800 Series Wireless Controllers Multicast DNS Denial of Service Vulnerability2020-09-24csaf · cisco_csafUS
A vulnerability in the multicast DNS (mDNS) feature of Cisco IOS XE Software for Cisco Catalyst 9800 Series Wireless Controllers could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. The vulnerability is due to improper validation of mDNS packets. An attacker could exploit this vulnerability by sending a crafted mDNS packet to an affected device. A successful exploit could cause a device to reload, resulting in a DoS condition. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. Note: The Cisco Catalyst 9800 Series Wireless Controllers default configuration is vulnerable. This advisory is part of the September 24, 2020, release of the Cisco IOS and IOS XE Software Security Advisory Bundled Publication, which includes 25 Cisco Security Advisories that describe 34 vulnerabilities. For a complete list of the advisories and links to them, see Cisco Event Response: September 2020 Semiannual Cisco IOS and IOS XE Software Security Advisory Bundled Publication ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-74268"].
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (7)
External citations — patches, advisories, analysis.
- http://www.nsfocus.net/vulndb/49456cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2020-3359cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-mdns-dos-3tH6cA9Jcnnvd
- https://vigilance.fr/vulnerability/Cisco-IOS-IOS-XE-multiple-vulnerabilities-33416cnnvd
- https://www.auscert.org.au/bulletins/ESB-2020.3279/cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-mdns-dos-3tH6cA9Jenisa_euvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-mdns-dos-3tH6cA9JVendor Advisorynvd
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