CVE-2022-20927 Denial of service in Cisco Adaptive Security Appliance (ASA) Software
An authenticated remote attacker can cause a denial of service on Cisco ASA and FTD devices by forcing connections to malicious SSL/TLS servers.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2022-20927?
CVE-2022-20927 is a high-severity denial of service vulnerability in Cisco Adaptive Security Appliance Software, published on 10 Nov 2022. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A vulnerability in the SSL/TLS client of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an authenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper memory management when a device initiates SSL/TLS connections. An attacker could exploit this vulnerability by ensuring that the device will connect to an SSL/TLS server that is using specific encryption parameters. A successful exploit could allow the attacker to cause the affected device to unexpectedly reload, resulting in a DoS condition.
Weakness: CWE-120
Which versions are affected by CVE-2022-20927?
It affects 3 products.
Products include Cisco Adaptive Security Appliance Software, Cisco Firepower Services Software for Asa, Cisco Secure Firewall Threat Defense.
How do I fix CVE-2022-20927?
No fix has been published for CVE-2022-20927 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2022-20927 being exploited?
There is no known exploitation of CVE-2022-20927 in the wild and no public exploit code.
Other vulnerabilities in Cisco Adaptive Security Appliance Software
- CVE-2025-20333 Cisco Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) Buffer Overflow
- CVE-2016-6366 Cisco Adaptive Security Appliance (ASA) SNMP Buffer Overflow
- CVE-2026-20349 Cisco Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) Heap Inspection
- CVE-2024-20353 Cisco ASA and FTD Denial of Service
- CVE-2016-6367 Cisco Adaptive Security Appliance (ASA) CLI Remote Code Execution
All Cisco Adaptive Security Appliance Software vulnerabilities
Sources
Also known as GHSA-4g76-357g-vr49.