cbcvebase.
CVE-2021-34793
published 2021-10-27

CVE-2021-34793: A vulnerability in the TCP Normalizer of Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software operating in transparent…

PriorityP348high8.6CVSS 3.1
AVNACLPRNUINSCCNINAH
EPSS
0.65%
47.0th percentile
A vulnerability in the TCP Normalizer of Cisco Adaptive Security Appliance (ASA) Software and Firepower Threat Defense (FTD) Software operating in transparent mode could allow an unauthenticated, remote attacker to poison MAC address tables, resulting in a denial of service (DoS) vulnerability. This vulnerability is due to incorrect handling of certain TCP segments when the affected device is operating in transparent mode. An attacker could exploit this vulnerability by sending a crafted TCP segment through an affected device. A successful exploit could allow the attacker to poison the MAC address tables in adjacent devices, resulting in network disruption.

Affected

18 ranges
VendorProductVersion rangeFixed in
ciscoadaptive_security_appliance< 9.8.4.409.8.4.40
ciscoadaptive_security_appliance
ciscoadaptive_security_appliance_software>= 9.13.0 < 9.14.3.99.14.3.9
ciscoadaptive_security_appliance_software>= 9.15.0 < 9.15.1.179.15.1.17
ciscoadaptive_security_appliance_software>= 9.16.0 < 9.16.2.39.16.2.3
ciscoadaptive_security_appliance_software>= 9.9.0 < 9.12.4.299.12.4.29
ciscoasa_5505_firmware
ciscoasa_5512-x_firmware
ciscoasa_5515-x_firmware
ciscoasa_5525-x_firmware
ciscoasa_5545-x_firmware
ciscoasa_5555-x_firmware
ciscoasa_5580_firmware
ciscoasa_5585-x_firmware
ciscocisco_adaptive_security_appliance_software
ciscofirepower_threat_defense< 6.4.0.136.4.0.13
ciscofirepower_threat_defense>= 6.5.0 < 6.6.56.6.5
ciscofirepower_threat_defense>= 6.7.0 < 6.7.0.36.7.0.3

CVSS provenance

nvdv3.18.6HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P
vendor_cisco8.6HIGH
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