ACTIVELY EXPLOITED
CVE-2024-20353: Cisco ASA and FTD Denial of Service Vulnerability
| Vendor | Cisco |
|---|---|
| Product | Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD) |
| Actively exploited | Yes |
| Added to CISA KEV | 24 Apr 2024 |
| CISA federal deadline | 1 May 2024 |
| Weakness (CWE) | CWE-835 |
Required action (CISA's text)
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Description (NVD)
Cisco Adaptive Security Appliance (ASA) and Firepower Threat Defense (FTD) contain an infinite loop vulnerability that can lead to remote denial of service condition.
SOURCES
Other Cisco flaws
- CVE-2026-20320: Cisco BroadWorks Improper Restriction of XML External Entity Reference Vulnerability
- CVE-2026-76418: Cisco Secure Firewall ASA Software and Cisco Secure FTD Software Unchecked Return Value to NULL Pointer Dereference Vulnerability
- CVE-2026-76519: Cisco Secure Email Gateway Relative Path Traversal Vulnerability
- CVE-2026-76504: Cisco Catalyst SD-WAN Manager Hex Encoding Vulnerability
- CVE-2026-76460: Cisco Identity Services Engine Incorrect Use of Privileged APIs Vulnerability
Data from NVD, CISA KEV, FIRST EPSS and vendor advisories. Updated 10 Nov 2026.