Out-of-bounds write in Cisco Systems, Inc products - CVE-2021-40118
Published: October 28, 2021
Vulnerability identifier: #VU57757
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2021-40118
CWE-ID: CWE-787
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.
The vulnerability exists due to a boundary error when processing HTTP requests in the SSL VPN interface. A remote attacker can create a specially crafted HTTP reuqst, trigger out-of-bounds write and perform a denial of service (DoS) attack.
Affected software
ASA 5500-X Series Firewalls
Cisco Secure Firewall Threat Defense (FTD)
Cisco Secure Firewall Adaptive Security Appliance (ASA)
Cisco Secure Firewall Threat Defense (FTD)
Cisco Secure Firewall Adaptive Security Appliance (ASA)
How to mitigate CVE-2021-40118
Install updates from vendor's website.
Cisco Secure Firewall Threat Defense (FTD) - addressed in versions 6.4.0.13, 6.6.5, 6.7.0.3, 7.0.1
Cisco Secure Firewall Adaptive Security Appliance (ASA) - addressed in versions 9.8.4.40, 9.12.4.29, 9.14.3.9, 9.15.1.17, 9.16.2.3
Cisco Secure Firewall Adaptive Security Appliance (ASA) - addressed in versions 9.8.4.40, 9.12.4.29, 9.14.3.9, 9.15.1.17, 9.16.2.3