A flaw in the OSPF implementation of Cisco Secure Firewall ASA and FTD software leads to heap corruption when parsing OSPF packets. The vulnerability is triggered by crafted packets that exploit a buffer overflow (CWE‑119). A successful exploitation causes the device to reload unexpectedly, resulting in a denial‑of‑service condition. The flaw requires the attacker to possess the OSPF secret key, so it is an authenticated vulnerability.

Affected products include Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software. Specific versions are not enumerated in the advisory, so all currently deployed releases may be impacted until Cisco releases a patch.

The CVSS v3 score of 6.8 classifies the issue as medium severity, while the EPSS score of less than 1% indicates a very low probability of exploitation in the wild. The vulnerability is not listed in the CISA KEV catalog. An attacker would need to be on an adjacent network segment and possess OSPF authentication credentials to send the malicious OSPF packets, making the attack feasible for insiders or compromised neighboring devices.