high
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 1109-4p Integrated Services Router
Cisco 1100 Integrated Services Router
Cisco 1100-4g/6g Integrated Services Router
Cisco 1101 Integrated Services Router
Cisco IR 1101
Cisco 1109 Integrated Services Router
Cisco 1109 Integrated Services Router
Cisco 1109 Integrated Services Router
Cisco 1111x-8p
Cisco 111x 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 Firmware
Cisco Aironet 1542D
Cisco Aironet 1542i Firmware
Cisco Aironet 1560
Cisco Aironet 1562 firmware
Cisco Aironet 1562E Firmware
Cisco Aironet 1562 firmware
Cisco Aironet 1800 Firmware
Cisco Aironet 1800i Firmware
Cisco Aironet 1810
Cisco Aironet 1810w
Cisco Aironet 1815 Firmware
Cisco Aironet 1815 Firmware
Cisco Aironet 1830i Firmware
Cisco Aironet 1830E Firmware
Cisco Aironet 1830i Access Point
Cisco Aironet 1840i Firmware
Cisco Aironet 1850i Firmware
Cisco Aironet 1850e Access Point
Cisco Aironet 1850i Access Point
Cisco Aironet 2800
Cisco Aironet 2800e Firmware
Cisco Aironet 2800 Firmware
Cisco Aironet 3800p
Cisco Aironet 3800E Firmware
Cisco Aironet 3800 Firmware
Cisco Aironet 3800P Firmware
Cisco Aironet 4800 Firmware
Cisco Catalyst 9100 firmware
Cisco Catalyst 9000 Family Switches
Cisco Catalyst 9105 Firmware
Cisco Catalyst 9105AX
Cisco Catalyst 9115 Firmware
Cisco Catalyst 9115axi
Cisco Catalyst 9115 AP Firmware
Cisco Catalyst 9115AXI Firmware
Cisco Catalyst 9117 Firmware
Cisco Catalyst 9117
Cisco Catalyst 9117AX
Cisco Catalyst 9120AXI Firmware
Cisco Catalyst 9120
Cisco Catalyst 9120 Firmware
Cisco Catalyst 9120 Firmware
Cisco Catalyst 9120 Firmware
Cisco Catalyst 9124 Firmware
Cisco Catalyst 9124 Firmware
Cisco Catalyst 9124 Firmware
Cisco Catalyst 9130 Firmware
Cisco Catalyst 9130
Cisco Catalyst 9130 Firmware
Cisco Catalyst 9130 Firmware
Cisco Catalyst IW6300 DC Firmware
Cisco Catalyst IW6300
Cisco Catalyst IW6300
Cisco Catalyst IW6300

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Reference Links

Frequently Asked Questions

  • What is the severity of CVE-2021-34740?

    CVE-2021-34740 is rated as a medium severity vulnerability due to its potential to cause a denial of service condition.

  • How do I fix CVE-2021-34740?

    To remediate CVE-2021-34740, users should upgrade to the fixed versions provided in Cisco's security advisory.

  • Which Cisco products are affected by CVE-2021-34740?

    CVE-2021-34740 affects specific versions of the Cisco Aironet Access Point software.

  • What type of attack does CVE-2021-34740 allow?

    CVE-2021-34740 allows an unauthenticated adjacent attacker to cause a reload of the affected device.

  • What impact does CVE-2021-34740 have on Cisco devices?

    The impact of CVE-2021-34740 on Cisco devices is a potential denial of service due to device reloads.

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