CVE-2018-15397 Cisco Adaptive Security Appliance IPsec VPN Denial of Service Vulnerability
Remote attackers can crash Cisco ASA or FTD devices by sending malicious IPsec TFC traffic, causing a denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2018-15397?
CVE-2018-15397 is a medium-severity denial of service vulnerability in Cisco Adaptive Security Appliance Software, published on 5 Oct 2018. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
A vulnerability in the implementation of Traffic Flow Confidentiality (TFC) over IPsec functionality in Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to restart unexpectedly, resulting in a denial of service (DoS) condition. The vulnerability is due to an error that may occur if the affected software renegotiates the encryption key for an IPsec tunnel when certain TFC traffic is in flight. An attacker could exploit this vulnerability by sending a malicious stream of TFC traffic through an established IPsec tunnel on an affected device. A successful exploit could allow the attacker to cause a daemon process on the affected device to crash, which could cause the device to crash and result in a DoS condition.
Weakness: CWE-320
Which versions are affected by CVE-2018-15397?
It affects 2 products.
Products include Cisco Adaptive Security Appliance Software, Cisco Secure Firewall Management Center.
How do I fix CVE-2018-15397?
No fix has been published for CVE-2018-15397 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-2018-15397 being exploited?
There is no known exploitation of CVE-2018-15397 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-rhcj-jwww-2qpj.