How severe is CVE-2021-1615?

CVE-2021-1615 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-2021-1615 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-1615?

CVE-2021-1615 affects Cisco Embedded Wireless Controller. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-1615?

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-2021-1615 published?

CVE-2021-1615 was published on 2021-09-23 and last updated on 2026-06-17.

CVE-2021-1615

CVE-2021-1615 is a high-severity vulnerability in Cisco Embedded Wireless Controller 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-410.

Key facts

Severity: High (CVSS 3.x base score 8.6)
CVSS v2: 5.0
EPSS exploit prediction: 1% (67th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-410
Affected product: Cisco Embedded Wireless Controller
Published: 2021-09-23
Last modified: 2026-06-17

Description

A vulnerability in the packet processing functionality of Cisco Embedded Wireless Controller (EWC) Software for Catalyst Access Points (APs) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected AP. This vulnerability is due to insufficient buffer allocation. An attacker could exploit this vulnerability by sending crafted traffic to an affected device. A successful exploit could allow the attacker to exhaust available resources and cause a DoS condition on an affected AP, as well as a DoS condition for client traffic traversing the AP.

Frequently asked questions

What is CVE-2021-1615?: A vulnerability in the packet processing functionality of Cisco Embedded Wireless Controller (EWC) Software for Catalyst Access Points (APs) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected AP. This vulnerability is due to insufficient buffer allocation. An attacker could exploit this vulnerability by sending crafted traffic to an affected device. A successful exploit could allow the attacker to exhaust available resources and cause a DoS condition on an affected AP, as well as a DoS condition for client traffic traversing the AP.
How severe is CVE-2021-1615?: CVE-2021-1615 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-2021-1615 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (67th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-1615?: CVE-2021-1615 affects Cisco Embedded Wireless Controller. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-1615?: 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-2021-1615 published?: CVE-2021-1615 was published on 2021-09-23 and last updated on 2026-06-17.

References

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-iosxe-ewc-dos-g6JruHRT

Affected products (1)

cpe:2.3:a:cisco:embedded_wireless_controller:*:*:*:*:*:*:*:*

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