How severe is CVE-2022-20856?

CVE-2022-20856 has a CVSS 3.x base score of 8.6, 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-2022-20856 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2022-20856?

CVE-2022-20856 affects Cisco Ios Xe. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2022-20856?

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-2022-20856 published?

CVE-2022-20856 was published on 2022-09-30 and last updated on 2026-06-17.

CVE-2022-20856

CVE-2022-20856 is a high-severity vulnerability in Cisco Ios Xe with a CVSS 3.x base score of 8.6. 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-664.

Key facts

Severity: High (CVSS 3.x base score 8.6)
EPSS exploit prediction: 1% (61st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-664
Affected product: Cisco Ios Xe
Published: 2022-09-30
Last modified: 2026-06-17

Description

A vulnerability in the processing of Control and Provisioning of Wireless Access Points (CAPWAP) Mobility messages in Cisco IOS XE Wireless Controller Software for the Catalyst 9000 Family could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to a logic error and improper management of resources related to the handling of CAPWAP Mobility messages. An attacker could exploit this vulnerability by sending crafted CAPWAP Mobility packets to an affected device. A successful exploit could allow the attacker to exhaust resources on the affected device. This would cause the device to reload, resulting in a DoS condition.

Frequently asked questions

What is CVE-2022-20856?: A vulnerability in the processing of Control and Provisioning of Wireless Access Points (CAPWAP) Mobility messages in Cisco IOS XE Wireless Controller Software for the Catalyst 9000 Family could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to a logic error and improper management of resources related to the handling of CAPWAP Mobility messages. An attacker could exploit this vulnerability by sending crafted CAPWAP Mobility packets to an affected device. A successful exploit could allow the attacker to exhaust resources on the affected device. This would cause the device to reload, resulting in a DoS condition.
How severe is CVE-2022-20856?: CVE-2022-20856 has a CVSS 3.x base score of 8.6, 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-2022-20856 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (61st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2022-20856?: CVE-2022-20856 affects Cisco Ios Xe. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2022-20856?: 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-2022-20856 published?: CVE-2022-20856 was published on 2022-09-30 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-c9800-mob-dos-342YAc6J

Affected products (1)

cpe:2.3:o:cisco:ios_xe:17.3.4c:*:*:*:*:*:*:*

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