Buffer overflow in Cisco Adaptive Security Appliance Software

CVE-2026-20024

A vulnerability in the OSPF protocol of Cisco Secure Firewall ASA Software and Cisco Secure FTD Software could allow an authenticated, adjacent attacker to cause an affected device to reload unexpectedly, resulting in a DoS condition. To exploit this vulnerability, the attacker must have the OSPF secret key. This vulnerability is due to heap corruption in OSPF when parsing packets. An attacker could exploit this vulnerability by sending crafted packets to the OSPF service. A successful exploit could allow the attacker to corrupt the heap, causing the affected device to reload, resulting in a DoS condition.

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 6.8 (Medium). Vector: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H.

EPSS exploit prediction

EPSS: 0.002 (8.7th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 9th percentile — 8.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-20024: held from 0.002 to 0.002.

EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-20024?
CVE-2026-20024 is a medium-severity vulnerability in Cisco Adaptive Security Appliance Software, classified under Improper Restriction of Operations within the Bounds of a Memory Buffer. CVSS score: 6.8/10. Published 2026-03-04.
How severe is CVE-2026-20024?
Medium severity. CVSS v3 base score is 6.8 out of 10.