CVE-2019-1834
lowpriority · track · 26EPSS 0.006 · 50 %ileEURUUSEPSS · scored 2026-10-27
A vulnerability in the internal packet processing of Cisco Aironet Series Access Points (APs) could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected AP if the switch interface where the AP is connected has port security configured. The vulnerability exists because the AP forwards some malformed wireless client packets outside of the Control and Provisioning of Wireless Access Points (CAPWAP) tunnel. An attacker could exploit this vulnerability by sending crafted wireless packets to an affected AP. A successful exploit could allow the attacker to trigger a security violation on the adjacent switch port, which could result in a DoS condition. Note: Though the Common Vulnerability Scoring System (CVSS) score corresponds to a High Security Impact Rating (SIR), this vulnerability is considered Medium because a workaround is available and exploitation requires a specific switch configuration. There are workarounds that address this vulnerability.
remediations
Vendor fix, mitigation, or workaround guidance, as published by each source.
A vendor fix is available.
- FixedCisco Aironet Access Point Softwarecisco_csaf
Cisco has released software updates that address this vulnerability.
https://software.cisco.com - WorkaroundCisco Aironet Access Point Softwarecisco_csaf
Administrators can configure the switch interface with port security to learn only one MAC address (the switch learns the AP MAC address during AP bootup) and, in case of a security violation, to drop any new learned MAC addresses. Using the CLI, configure the security violation mode to either protect or restrict, as in the following example: # configuration terminal # interface interface_id # switchport port-security violation {protect | restrict} Note: CLI commands may vary slightly by switch model.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–high · 3.3–7.4
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (21)
Products and version ranges known to be affected.
- cisco aironet access point firmware8.5 → 8.5.140.0nvdUScpe:2.3:o:cisco:aironet_access_point_firmware:*:*:*:*:*:*:*:*
- cisco aironet access point firmware= 8.5(131.0)nvdUScpe:2.3:o:cisco:aironet_access_point_firmware:*:*:*:*:*:*:*:*
- cisco aironet access point firmware8.6.101.0 → 8.8.111.0nvdUScpe:2.3:o:cisco:aironet_access_point_firmware:*:*:*:*:*:*:*:*
advisories (1)
Vendor and ecosystem advisories describing this.
- cisco-sa-20190417-air-ap-dosCisco Aironet Series Access Points Denial of Service Vulnerability2019-04-17csaf · cisco_csafUS
A vulnerability in the internal packet processing of Cisco Aironet Series Access Points (APs) could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition on an affected AP if the switch interface where the AP is connected has port security configured. The vulnerability exists because the AP forwards some malformed wireless client packets outside of the Control and Provisioning of Wireless Access Points (CAPWAP) tunnel. An attacker could exploit this vulnerability by sending crafted wireless packets to an affected AP. A successful exploit could allow the attacker to trigger a security violation on the adjacent switch port, which could result in a DoS condition. Note: Though the Common Vulnerability Scoring System (CVSS) score corresponds to a High Security Impact Rating (SIR), this vulnerability is considered Medium because a workaround is available and exploitation requires a specific switch configuration. There are workarounds that address this vulnerability. This advisory is available at the following link: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190417-air-ap-dos ["https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190417-air-ap-dos"]
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (14)
External citations — patches, advisories, analysis.
- http://www.cisco.com/cnnvd
- http://www.cisco.com/cisco/web/solutions/small_business/products/wireless/aironet_series_access_points/index.htmlcnnvd
- http://www.securityfocus.com/bid/108000cnnvd
- https://nvd.nist.gov/vuln/detail/CVE-2019-1834cnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190417-air-ap-cmdinjcnnvd
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20190417-air-ap-doscnnvd
- https://vigilance.fr/vulnerability/Cisco-Aironet-denial-of-service-via-Malformed-Wireless-Client-Packets-29078cnnvd
- https://www.auscert.org.au/bulletins/79278cnnvd
Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.
Free scan