CVE-2021-34770
highpriority · track · 40EPSS 0.030 · 87 %ileEURUUSEPSS · scored 2026-10-27
A vulnerability in the Control and Provisioning of Wireless Access Points (CAPWAP) protocol processing of Cisco IOS XE Software for Cisco Catalyst 9000 Family Wireless Controllers could allow an unauthenticated, remote attacker to execute arbitrary code with administrative privileges or cause a denial of service (DoS) condition on an affected device. The vulnerability is due to a logic error that occurs during the validation of CAPWAP packets. An attacker could exploit this vulnerability by sending a crafted CAPWAP packet to an affected device. A successful exploit could allow the attacker to execute arbitrary code with administrative privileges or cause the affected device to crash and reload, resulting in a DoS condition.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- Fixed16.10.1cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.10.1ecisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.10.1scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - 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 - Fixed16.12.1cisco_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 - Fixed16.12.2scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.12.2tcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.12.3cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.12.3scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.12.4cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed16.12.4acisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed17.1.1cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed17.1.1scisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed17.1.1tcisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed17.1.2cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed17.1.3cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed17.2.1cisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed17.2.1acisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - Fixed17.3.1cisco_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⚠ sources disagree · high–critical · 9–10
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (58)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-ewlc-capwap-rce-LYgj8KfCisco IOS XE Software for Catalyst 9000 Family Wireless Controllers CAPWAP Remote Code Execution Vulnerability2021-09-22csaf · cisco_csafUS
A vulnerability in the Control and Provisioning of Wireless Access Points (CAPWAP) protocol processing of Cisco IOS XE Software for Cisco Catalyst 9000 Family Wireless Controllers could allow an unauthenticated, remote attacker to execute arbitrary code with administrative privileges or cause a denial of service (DoS) condition on an affected device. The vulnerability is due to a logic error that occurs during the validation of CAPWAP packets. An attacker could exploit this vulnerability by sending a crafted CAPWAP packet to an affected device. A successful exploit could allow the attacker to execute arbitrary code with administrative privileges or cause the affected device to crash and reload, resulting in a DoS condition. Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability. This advisory is part of the September 2021 release of the Cisco IOS and IOS XE Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see Cisco Event Response: September 2021 Semiannual Cisco IOS and IOS XE Software Security Advisory Bundled Publication. ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-74581"]
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (8)
External citations — patches, advisories, analysis.
- https://nvd.nist.gov/vuln/detail/CVE-2021-34770cnnvd
- https://tools.cisco.com/Patchcnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ewlc-capwap-rce-LYgj8Kfcnnvd
- https://vigilance.fr/vulnerability/Cisco-IOS-XE-code-execution-via-CAPWAP-36494cnnvd
- https://www.auscert.org.au/bulletins/ESB-2021.3180cnnvd
- https://www.cybersecurity-help.cz/vdb/SB2021092409cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ewlc-capwap-rce-LYgj8Kfenisa_euvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ewlc-capwap-rce-LYgj8KfVendor Advisorynvd
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