CVE-2026-20022
A vulnerability in the OSPF protocol of Cisco Secure Firewall ASA Software and Cisco Secure FTD...
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.
Attack profile
How easy it is to exploit
- Attack vector
- Adjacent network
- Complexity
- High
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
6.1
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.
- Record
CVE-2026-20022- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H - Weakness
- CWE-823
- Updated
- 2026-11-02
EUVDEUVD-2026-9479
6.1
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.
- Record
EUVD-2026-9479- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-99cr-qjpc-34g3
6.1
A vulnerability in the OSPF protocol of Cisco Secure Firewall ASA Software and Cisco Secure FTD...
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.
- Record
GHSA-99cr-qjpc-34g3- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H - Weakness
- CWE-823
- Updated
- 2026-11-02
NVD
6.1
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.
- Record
CVE-2026-20022- CVSS 3.1
- 6.1 Medium
CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:C/C:N/I:N/A:H - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-823
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-20022 is a medium vulnerability (CVSS 6.1) in Cisco Adaptive Security Appliance Software, published March 4, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.21%, the 11th percentile. No source names a fixed version.