7.4
CWE
401
Advisory Published
Updated

CVE-2021-34740: Cisco Aironet Access Points WLAN Control Protocol Packet Buffer Leak Denial of Service Vulnerability

First published: Thu Sep 23 2021(Updated: )

A vulnerability in the WLAN Control Protocol (WCP) implementation for Cisco Aironet Access Point (AP) software could allow an unauthenticated, adjacent attacker to cause a reload of an affected device, resulting in a denial of service (DoS) condition. This vulnerability is due to incorrect error handling when an affected device receives an unexpected 802.11 frame. An attacker could exploit this vulnerability by sending certain 802.11 frames over the wireless network to an interface on an affected AP. A successful exploit could allow the attacker to cause a packet buffer leak. This could eventually result in buffer allocation failures, which would trigger a reload of the affected device.

Credit: ykramarz@cisco.com

Affected SoftwareAffected VersionHow to fix
Cisco Access Point Software>=8.10.0<8.10.162.0
Cisco Access Point Software=17.2
Cisco Access Point Software=17.3
Cisco 1100-4g\/6g Integrated Services Router
Cisco 1100-4p Integrated Services Router
Cisco 1100-8p Integrated Services Router
Cisco 1100 Series Integrated Services Router
Cisco 1101-4p Integrated Services Router
Cisco 1101 Integrated Services Router
Cisco 1109-2p
Cisco 1109-4p Integrated Services Router
Cisco 1109 Integrated Services Router
Cisco 1111x-8p Integrated Services Router
Cisco 1111x Integrated Services Router
Cisco 111x Integrated Services Router
Cisco 1120 Integrated Services Router
Cisco 1160 Integrated Services Router
Cisco 6300 Series Access Points Firmware
Cisco Aironet 1540
Cisco Aironet 1542d
Cisco Aironet 1542i
Cisco Aironet 1560
Cisco Aironet 1562 firmware
Cisco Aironet 1562E Firmware
Cisco Aironet 1562 firmware
Cisco Aironet 1800
Cisco Aironet 1800i
Cisco Aironet 1810
Cisco Aironet 1810w
Cisco Aironet 1815
Cisco Aironet 1815i
Cisco Aironet 1830i Firmware
Cisco Aironet 1830E Firmware
Cisco Aironet 1830i Firmware
Cisco Aironet 1840i Firmware
Cisco Aironet 1850i Firmware
Cisco Aironet 1850E Firmware
Cisco Aironet 1850i Firmware
Cisco Aironet 2800
Cisco Aironet 2800e
Cisco Aironet 2800i
Cisco Aironet 3800p
Cisco Aironet 3800E Firmware
Cisco Aironet 3800i
Cisco Aironet 3800P Firmware
Cisco Aironet 4800 Firmware
Cisco Catalyst 9100 firmware
Cisco Catalyst 9000 Family
Cisco Catalyst 9105AX
Cisco Catalyst 9105AXW
Cisco Catalyst 9115axe
Cisco Catalyst 9115axi
Cisco Catalyst 9115AX
Cisco Catalyst 9115AX
Cisco Catalyst 9117AX
Cisco Catalyst 9117
Cisco Catalyst 9117AX
Cisco Catalyst 9120
Cisco Catalyst 9120
Cisco Catalyst 9120AXE Firmware
Cisco Catalyst 9120axi
Cisco Catalyst 9120axp
Cisco Catalyst 9124
Cisco Catalyst 9124
Cisco Catalyst 9124
Cisco Catalyst 9130
Cisco Catalyst 9130
Cisco Catalyst 9130AXE
Cisco Catalyst 9130
Cisco Catalyst IW6300
cisco catalyst iw6300 Ac
cisco catalyst iw6300 dc
cisco catalyst iw6300 dcw

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