CVE-2021-40118
HIGHCisco ASA & FTD Unauthenticated DoS via HTTPS Request Parsing
Title source: llmDescription
A vulnerability in the web services interface of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to trigger a denial of service (DoS) condition. This vulnerability is due to improper input validation when parsing HTTPS requests. An attacker could exploit this vulnerability by sending a malicious HTTPS request to an affected device. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition.
References (1)
Core 1
Core References
Vendor Advisory vendor-advisory
x_refsource_cisco
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-asafdt-webvpn-dos-KSqJAKPA
Scores
CVSS v3
8.6
EPSS
0.0026
EPSS Percentile
49.7%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-121
CWE-787
Status
published
Products (43)
cisco/adaptive_security_appliance
< 9.8.4.40
cisco/adaptive_security_appliance_software
9.9.0 - 9.12.4.29
cisco/asa_5505_firmware
009.012\(004.024\)
cisco/asa_5505_firmware
009.015\(001\)
cisco/asa_5505_firmware
009.015\(001.015\)
cisco/asa_5505_firmware
009.015\(001.016\)
cisco/asa_5505_firmware
009.016\(001\)
cisco/asa_5512-x_firmware
009.012\(004.024\)
cisco/asa_5512-x_firmware
009.015\(001\)
cisco/asa_5512-x_firmware
009.015\(001.015\)
... and 33 more
Published
Oct 27, 2021
Tracked Since
Feb 18, 2026