Medium severity · published Mar 4, 2026
CVE-2026-20022
A vulnerability in the OSPF protocol of Cisco Secure Firewall ASA Software and Cisco Secure FTD Software could allow an unauthenticated, adjacent attacker to cause an affected…
6.5
CVSS
0.2%
EPSS
No
On KEV
Description
A vulnerability in the OSPF protocol of Cisco Secure Firewall ASA Software and Cisco Secure FTD Software could allow an unauthenticated, adjacent attacker to cause an affected device to reload unexpectedly, resulting in a DoS condition when OSPF canonicalization debug is enabled by using the command debug ip ospf canon. This vulnerability is due to insufficient input validation when processing OSPF LSU packets. An attacker could exploit this vulnerability by sending crafted unauthenticated OSPF packets. A successful exploit could allow the attacker to write to memory outside of the packet data, causing the device to reload, resulting in a DoS condition.
CVSS vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Adjacent
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 9% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AS
Adaptive Security Appliance Software · Cisco
9.12.1; 9.12.1.2; 9.12.1.3; 9.12.2; 9.12.2.1; 9.12.2.4; +34 more · source: NVD
SF
Secure Firewall Threat Defense · Cisco
6.4.0; 6.4.0.1; 6.4.0.2; 6.4.0.3; 6.4.0.4; 6.4.0.5; +34 more · source: NVD
Affected product
AS
Adaptive Security Appliance Software
Cisco
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