CVE-2025-20333, CVE-2025-20362: Frequently Asked Questions About Zero-Day Cisco Adaptive Security Appliance (ASA) and Firewall Threat Defense (FTD) Vulnerabilities
Cisco published advisories and a supplemental post about three zero-day vulnerabilities, two of which were exploited in the wild by an advanced threat actor associated with the ArcaneDoor campaign.
Update September 25: This FAQ blog has been updated to include a reference to an NCSC report on associated malware linked to this campaign.
Tenable’s Research Special Operations (RSO) team has compiled this blog to answer Frequently Asked Questions (FAQ) regarding newly disclosed zero-day vulnerabilities in Cisco Adaptive Security Appliance (ASA) Software and Firewall Threat Defense (FTD) Software that were exploited.
FAQ
When were these vulnerabilities first disclosed?
On September 25, Cisco published advisories [ 1 , 2 , 3 ] and a supplemental post regarding three zero-day vulnerabilities in Cisco Adaptive Security Appliance (ASA) Software, Firewall Threat Defense (FTD) Software, IOS XE Software, and IOS XR Software.
What are the vulnerabilities that were disclosed?
The following three vulnerabilities were disclosed. Two (CVE-2025-20333, CVE-2025-20362) were exploited in the wild.
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