Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense
CVE-2025-20362
Cisco Secure Firewall Adaptive Security (ASA) Appliance and Secure Firewall Threat Defense (FTD) Software VPN Web Server contain a missing authorization vulnerability. This vulnerability could be chained with CVE-2025-20333.
What this means for your business
- It affects Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense. It matters if your company, or a supplier that handles your data, runs it.
- Attackers are already using it. CISA added it to its list of flaws used in real attacks on 25 September 2025.
- FIRST's prediction model gives it a 87% chance of attack attempts being seen in the next 30 days, ranking above 99% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Cisco Secure Firewall Adaptive Security Appliance and Secure Firewall Threat Defense.
- 2If you do, follow CISA's required action below. No patch reference has been published yet.
- 3Treat it as urgent. US federal agencies must fix it by 26 September 2025. That deadline does not apply to private companies, but it shows how seriously CISA takes it.
- 4Because attackers have used it, check the affected systems for signs of a break-in, not only for the update.
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Required action
The KEV due date refers to the deadline by which FCEB agencies are expected to review and begin implementing the guidance outlined in Emergency Directive (ED) 25-03 (URL listed below in Notes). Agencies must follow the mitigation steps provided by CISA (URL listed below in Notes) and vendor’s instructions (URL listed below in Notes). Adhere to the applicable BOD 22-01 guidance for cloud services or discontinue use of the product if mitigations are not available.
CISA’s wording, unedited. The notes it mentions are in CISA’s catalogue entry.
Scoring
- CVSS
- Not yet scored
Dates
- Published
- 2025-09-25
- Added to KEV
- 2025-09-25
- Remediation due
- 2025-09-26
- Sources
- CISA KEV