OSPF update packet processing buffer overflow DoS in Cisco Secure Firewall ASA/FTD
CVE-2026-20020 is a denial-of-service vulnerability in the OSPF protocol implementation of Cisco Secure Firewall ASA Software and Cisco Secure FTD Software. The issue is caused by insufficient input validation while processing OSPF update packets, which allows an adjacent attacker to send crafted OSPF update packets that trigger a buffer overflow condition. Successful exploitation causes the affected device to reload unexpectedly, resulting in a denial-of-service condition. If OSPF authentication is enabled, exploitation additionally requires knowledge of the configured OSPF authentication secret key.
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Exploits
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Recent activity
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Cross-references every affected SKU, including bundled OEM variants.
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