CVE-2025-20263 Memory corruption in Cisco Adaptive Security Appliance (ASA) Software
Unauthenticated remote attackers can cause a denial of service via buffer overflow in Cisco ASA and FTD web services.
- 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-2025-20263?
CVE-2025-20263 is a high-severity memory corruption 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 web services interface of Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a buffer overflow on an affected system. This vulnerability is due to insufficient boundary checks for specific data that is provided to the web services interface of an affected system. An attacker could exploit this vulnerability by sending a crafted HTTP request to the affected system. A successful exploit could allow the attacker to cause a buffer overflow condition on the affected system, which could cause the system to reload, resulting in a denial of service (DoS) condition.
Weakness: CWE-680
Which versions are affected by CVE-2025-20263?
How do I fix CVE-2025-20263?
No fix has been published for CVE-2025-20263 yet. Limit exposure of the affected software until one is available.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2025-20263 being exploited?
There is no known exploitation of CVE-2025-20263 in the wild and no public exploit code.
Sources
Also known as GHSA-8qmf-r775-gfcm.