CVE-2025-20219 Auth bypass in Cisco Adaptive Security Appliance (ASA) Software
Unauthenticated remote attackers can bypass access control rules to send blocked traffic to loopback interfaces on Cisco ASA and FTD devices.
- 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-2025-20219?
CVE-2025-20219 is a medium-severity authentication bypass vulnerability in Cisco Adaptive Security Appliance (ASA) Software, published on 14 Aug 2025. 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 access control rules for loopback interfaces in Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to send traffic that should have been blocked to a loopback interface. This vulnerability is due to improper enforcement of access control rules for loopback interfaces. An attacker could exploit this vulnerability by sending traffic to a loopback interface on an affected device. A successful exploit could allow the attacker to bypass configured access control rules and send traffic that should have been blocked to a loopback interface on the device.
Weakness: CWE-284
Which versions are affected by CVE-2025-20219?
How do I fix CVE-2025-20219?
No fix has been published for CVE-2025-20219 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2025-20219 being exploited?
There is no known exploitation of CVE-2025-20219 in the wild and no public exploit code.
Sources
Also known as GHSA-8x2f-w8fv-gqcm.