How severe is CVE-2022-20854?

CVE-2022-20854 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2022-20854 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-20854?

CVE-2022-20854 primarily affects Cisco Secure Firewall Management Center. In total, 36 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2022-20854?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2022-20854 published?

CVE-2022-20854 was published on 2022-11-15 and last updated on 2026-06-17.

CVE-2022-20854

CVE-2022-20854 is a high-severity vulnerability in Cisco Secure Firewall Management Center with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-755.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (54th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-755
Affected product: Cisco Secure Firewall Management Center
Published: 2022-11-15
Last modified: 2026-06-17

Description

A vulnerability in the processing of SSH connections of Cisco Firepower Management Center (FMC) and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper error handling when an SSH session fails to be established. An attacker could exploit this vulnerability by sending a high rate of crafted SSH connections to the instance. A successful exploit could allow the attacker to cause resource exhaustion, resulting in a reboot on the affected device.

Frequently asked questions

What is CVE-2022-20854?: A vulnerability in the processing of SSH connections of Cisco Firepower Management Center (FMC) and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to improper error handling when an SSH session fails to be established. An attacker could exploit this vulnerability by sending a high rate of crafted SSH connections to the instance. A successful exploit could allow the attacker to cause resource exhaustion, resulting in a reboot on the affected device.
How severe is CVE-2022-20854?: CVE-2022-20854 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2022-20854 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-20854?: CVE-2022-20854 primarily affects Cisco Secure Firewall Management Center. In total, 36 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2022-20854?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2022-20854 published?: CVE-2022-20854 was published on 2022-11-15 and last updated on 2026-06-17.

References

https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-fmc-dos-OwEunWJN

Affected products (36)

cpe:2.3:a:cisco:secure_firewall_management_center:*:*:*:*:*:*:*:*
cpe:2.3:a:cisco:secure_firewall_management_center:6.2.1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:secure_firewall_management_center:6.6.0:*:*:*:*:*:*:*
cpe:2.3:a:cisco:secure_firewall_management_center:6.6.0.1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:secure_firewall_management_center:6.6.1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:secure_firewall_management_center:6.6.3:*:*:*:*:*:*:*
cpe:2.3:a:cisco:secure_firewall_management_center:6.6.4:*:*:*:*:*:*:*
cpe:2.3:a:cisco:secure_firewall_management_center:6.6.5:*:*:*:*:*:*:*
cpe:2.3:a:cisco:secure_firewall_management_center:6.6.5.1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:secure_firewall_management_center:6.6.5.2:*:*:*:*:*:*:*
cpe:2.3:a:cisco:secure_firewall_management_center:7.0.0:*:*:*:*:*:*:*
cpe:2.3:a:cisco:secure_firewall_management_center:7.0.0.1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:secure_firewall_management_center:7.0.1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:secure_firewall_management_center:7.0.1.1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:secure_firewall_management_center:7.0.2:*:*:*:*:*:*:*
cpe:2.3:a:cisco:secure_firewall_management_center:7.0.2.1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:secure_firewall_management_center:7.0.3:*:*:*:*:*:*:*
cpe:2.3:a:cisco:secure_firewall_management_center:7.0.4:*:*:*:*:*:*:*
cpe:2.3:a:cisco:firepower_threat_defense:*:*:*:*:*:*:*:*
cpe:2.3:a:cisco:firepower_threat_defense:6.2.1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:firepower_threat_defense:6.6.0:*:*:*:*:*:*:*
cpe:2.3:a:cisco:firepower_threat_defense:6.6.0.1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:firepower_threat_defense:6.6.1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:firepower_threat_defense:6.6.3:*:*:*:*:*:*:*
cpe:2.3:a:cisco:firepower_threat_defense:6.6.4:*:*:*:*:*:*:*
cpe:2.3:a:cisco:firepower_threat_defense:6.6.5:*:*:*:*:*:*:*
cpe:2.3:a:cisco:firepower_threat_defense:6.6.5.1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:firepower_threat_defense:6.6.5.2:*:*:*:*:*:*:*
cpe:2.3:a:cisco:firepower_threat_defense:7.0.0:*:*:*:*:*:*:*
cpe:2.3:a:cisco:firepower_threat_defense:7.0.0.1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:firepower_threat_defense:7.0.1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:firepower_threat_defense:7.0.1.1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:firepower_threat_defense:7.0.2:*:*:*:*:*:*:*
cpe:2.3:a:cisco:firepower_threat_defense:7.0.2.1:*:*:*:*:*:*:*
cpe:2.3:a:cisco:firepower_threat_defense:7.0.3:*:*:*:*:*:*:*
cpe:2.3:a:cisco:firepower_threat_defense:7.0.4:*:*:*:*:*:*:*

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