Oct 20, 2026 · 17:58 UTC SEARCH
UNRATED KNOWN EXPLOITED
Vulnerability intelligence

CVE-2026-20349

VendorCisco
ProductSecure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD)
Known exploitedYes
Added to CISA KEVAugust 11, 2026
KEV due dateAugust 14, 2026
Known ransomware useNot identified by CISA

Cisco Secure Firewall Adaptive Security Appliance (ASA) and Secure Firewall Threat Defense (FTD) contain a heap inspection vulnerability that could allow an unauthenticated, remote attacker to cause the device to reload unexpectedly, resulting in a denial of service (DoS) condition.

Required action

Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

CISA KEV status

This vulnerability is listed in CISA’s Known Exploited Vulnerabilities Catalog. Known ransomware campaign use: Unknown.

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