CVE-2026-20336 Other in Cisco Secure Firewall Adaptive Security Appliance (ASA) Software

High 8.8 Published Updated

Cisco firewall software contains resource lifetime management flaws that could lead to denial of service, requiring a security hardening patch.

Exploited in the wild
Not known
Login needed
Not needed
Attackable
Local or same network only
Victim action needed
Not needed
Fix
None listed

What is CVE-2026-20336?

CVE-2026-20336 is a high-severity vulnerability in Cisco Secure Firewall Adaptive Security Appliance (ASA) Software, published on 16 Sep 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Secure Adaptive Security Appliance Software, Cisco Secure Firewall Threat Defense Software and Cisco Secure Firewall Management Center Software engineering team has conducted a comprehensive internal security review. This review resulted in a software hardening release that addresses multiple internally discovered vulnerabilities. The vulnerabilities tracked by CVE-2026-20336 are related to issues concerning improper control of a resource through its lifetime that are grouped under the Common Weakness Enumeration (CWE) Pillar CWE-664.

Weakness: CWE-664

Which versions are affected by CVE-2026-20336?

How do I fix CVE-2026-20336?

No fix has been published for CVE-2026-20336 yet. Limit exposure of the affected software until one is available.

Is CVE-2026-20336 being exploited?

There is no known exploitation of CVE-2026-20336 in the wild and no public exploit code.

Sources

Also known as GHSA-w3f5-j392-38wg.

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