CVE-2020-3510
highpriority · track · 34EPSS 0.014 · 72 %ileEURUUSEPSS · scored 2026-10-27
A vulnerability in the Umbrella Connector component of Cisco IOS XE Software for Cisco Catalyst 9200 Series Switches could allow an unauthenticated, remote attacker to trigger a reload, resulting in a denial of service condition on an affected device. The vulnerability is due to insufficient error handling when parsing DNS requests. An attacker could exploit this vulnerability by sending a series of malicious DNS requests to an Umbrella Connector client interface of an affected device. A successful exploit could allow the attacker to cause a crash of the iosd process, which triggers a reload of the affected device.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- Fixed16.12.1cisco_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 - Fixed16.12.2cisco_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 (10)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-iosxe-umbrella-dos-t2QMUX37Cisco IOS XE Software for Catalyst 9200 Series Switches Umbrella Connector Denial of Service Vulnerability2020-09-24csaf · cisco_csafUS
A vulnerability in the Umbrella Connector component of Cisco IOS XE Software for Cisco Catalyst 9200 Series Switches could allow an unauthenticated, remote attacker to trigger a reload, resulting in a denial of service condition on an affected device. The vulnerability is due to insufficient error handling when parsing DNS requests. An attacker could exploit this vulnerability by sending a series of malicious DNS requests to an Umbrella Connector client interface of an affected device. A successful exploit could allow the attacker to cause a crash of the iosd process, which triggers a reload of the affected device. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. 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/49413cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2020-3510cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxe-umbrella-dos-t2QMUX37cnnvd
- 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-iosxe-umbrella-dos-t2QMUX37enisa_euvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxe-umbrella-dos-t2QMUX37Vendor Advisorynvd
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