How severe is CVE-2020-3497?

CVE-2020-3497 has a CVSS 3.x base score of 7.4, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2020-3497 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-3497?

CVE-2020-3497 affects Cisco Ios Xe. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-3497?

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-2020-3497 published?

CVE-2020-3497 was published on 2020-09-24 and last updated on 2026-06-17.

CVE-2020-3497

CVE-2020-3497 is a high-severity vulnerability in Cisco Ios Xe with a CVSS 3.x base score of 7.4. 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-20.

Key facts

Severity: High (CVSS 3.x base score 7.4)
CVSS v2: 6.1
EPSS exploit prediction: 1% (40th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Ios Xe
Published: 2020-09-24
Last modified: 2026-06-17

Description

Multiple vulnerabilities in the Control and Provisioning of Wireless Access Points (CAPWAP) protocol processing of Cisco IOS XE Software for Cisco Catalyst 9800 Series Wireless Controllers could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition of an affected device. These vulnerabilities are due to insufficient validation of CAPWAP packets. An attacker could exploit these vulnerabilities by sending a malformed CAPWAP packet to an affected device. A successful exploit could allow the attacker to cause the affected device to crash and reload, resulting in a DoS condition on the affected device.

Frequently asked questions

What is CVE-2020-3497?: Multiple vulnerabilities in the Control and Provisioning of Wireless Access Points (CAPWAP) protocol processing of Cisco IOS XE Software for Cisco Catalyst 9800 Series Wireless Controllers could allow an unauthenticated, adjacent attacker to cause a denial of service (DoS) condition of an affected device. These vulnerabilities are due to insufficient validation of CAPWAP packets. An attacker could exploit these vulnerabilities by sending a malformed CAPWAP packet to an affected device. A successful exploit could allow the attacker to cause the affected device to crash and reload, resulting in a DoS condition on the affected device.
How severe is CVE-2020-3497?: CVE-2020-3497 has a CVSS 3.x base score of 7.4, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2020-3497 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-3497?: CVE-2020-3497 affects Cisco Ios Xe. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-3497?: 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-2020-3497 published?: CVE-2020-3497 was published on 2020-09-24 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-capwap-dos-TPdNTdyq

Affected products (1)

cpe:2.3:o:cisco:ios_xe:16.12.1:*:*:*:*:*:*:*

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