A memory leak in the IKEv2 packet parsing of Cisco Secure Firewall ASA and FTD creates a denial‑of‑service vulnerability. An unauthenticated remote attacker can send specially crafted IKEv2 packets that cause the device to consume memory until resources are exhausted, forcing a manual reload to restore services. The flaw provides no privilege escalation or data disclosure but cripples network availability for hosts depending on the affected appliance.

The flaw affects Cisco Secure Firewall ASA Software and Cisco Secure FTD Software, including all releases that have not yet applied the vendor fix. No specific version numbers are listed in the advisory, so any installation of these products that lacks the update is susceptible.

The advisory assigns a CVSS score of 5.8, indicating moderate severity, while the EPSS score is below 1 %, implying a very low likelihood of active exploitation. The vulnerability is not listed in the CISA KEV catalog, and the attack vector is inferred to be remote over the network via IKEv2 traffic. Attackers would need to send malicious IKEv2 packets to the appliance; no local access or special credentials are required.