CVE-2021-1565
CVE-2021-1565 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-415.
Key facts
- Severity: High (CVSS 3.x base score 8.6)
- CVSS v2: 5.0
- EPSS exploit prediction: 1% (66th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-415
- Affected product: Cisco Ios Xe
- Published:
- Last modified:
Description
Multiple vulnerabilities in the Control and Provisioning of Wireless Access Points (CAPWAP) protocol processing of Cisco IOS XE Software for Cisco Catalyst 9000 Family Wireless Controllers could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. These vulnerabilities are due to insufficient validation of CAPWAP packets. An attacker could exploit the 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.
Frequently asked questions
- What is CVE-2021-1565?
- Multiple vulnerabilities in the Control and Provisioning of Wireless Access Points (CAPWAP) protocol processing of Cisco IOS XE Software for Cisco Catalyst 9000 Family Wireless Controllers could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. These vulnerabilities are due to insufficient validation of CAPWAP packets. An attacker could exploit the 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.
- How severe is CVE-2021-1565?
- CVE-2021-1565 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-2021-1565 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (66th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-1565?
- CVE-2021-1565 primarily affects Cisco Ios Xe. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-1565?
- 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-2021-1565 published?
- CVE-2021-1565 was published on 2021-09-23 and last updated on 2026-06-17.
References
Affected products (9)
- cpe:2.3:o:cisco:ios_xe:3.15.1xbs:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:3.15.2xbs:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:17.3.1:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:17.3.2:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:17.4.1:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:ios_xe:17.5.1:*:*:*:*:*:*:*
- cpe:2.3:a:cisco:embedded_wireless_controller:*:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:catalyst_9800_firmware:17.3:*:*:*:*:*:*:*
- cpe:2.3:o:cisco:catalyst_9800_firmware:17.5.1:*:*:*:*:*:*:*
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