CISCO-SA-WLC-DOS-HNX5KGOM
Vulnerability from csaf_cisco - Published: 2026-03-25 16:00 - Updated: 2026-03-25 16:00Summary
Cisco IOS XE Wireless Controller Software for the Catalyst CW9800 Family CAPWAP Denial of Service Vulnerability
Notes
Summary: A vulnerability in the processing of Control and Provisioning of Wireless Access Points (CAPWAP) packets of Cisco IOS XE Wireless Controller Software for the Catalyst CW9800 Family could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device.
This vulnerability is due to improper handling of a malformed CAPWAP packet. An attacker could exploit this vulnerability by sending a malformed CAPWAP packet to an affected device. A successful exploit could allow the attacker to cause the affected device to reload unexpectedly, resulting in a DoS condition.
Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.
This advisory is part of the March 2026 release of the Cisco IOS and IOS XE Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see Cisco Event Response: March 2026 Semiannual Cisco IOS and IOS XE Software Security Advisory Bundled Publication ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-75297"].
Vulnerable Products: This vulnerability affects the following Cisco products if they are running a vulnerable release of Cisco IOS XE Wireless Controller Software, regardless of device configuration:
Catalyst CW9800H Wireless Controllers
Catalyst CW9800M Wireless Controllers
For information about which Cisco software releases are vulnerable, see the Fixed Software ["#fs"] section of this advisory.
Products Confirmed Not Vulnerable: Only products listed in the Vulnerable Products ["#vp"] section of this advisory are known to be affected by this vulnerability.
Cisco has confirmed that this vulnerability does not affect the following Cisco products:
Catalyst 9800 Embedded Wireless Controllers for Catalyst 9300, 9400, and 9500 Series Switches
Catalyst 9800-40 Wireless Controllers
Catalyst 9800-80 Wireless Controllers
Catalyst 9800-CL Wireless Controllers for Cloud
Catalyst 9800-L Wireless Controllers
Catalyst CW9800L Wireless Controllers
Embedded Wireless Controllers on Catalyst Access Points
IOS Software
IOS XR Software
NX-OS Software
WLC AireOS Software
Workarounds: There are no workarounds that address this vulnerability.
Fixed Software: Cisco considers any workarounds and mitigations (if applicable) to be temporary solutions until an upgrade to a fixed software release is available. To fully remediate this vulnerability and avoid future exposure as described in this advisory, Cisco strongly recommends that customers upgrade to the fixed software indicated in this advisory.
Cisco IOS and IOS XE Software
To help customers determine their exposure to vulnerabilities in Cisco IOS and IOS XE Software, Cisco provides the Cisco Software Checker ["https://sec.cloudapps.cisco.com/security/center/softwarechecker.x"]. This tool identifies any Cisco security advisories that impact a specific software release and the earliest release that fixes the vulnerabilities that are described in each advisory (“First Fixed”). If applicable, the tool also returns the earliest release that fixes all the vulnerabilities that are described in all the advisories that the Software Checker identifies (“Combined First Fixed”).
To use the tool, go to the Cisco Software Checker ["https://sec.cloudapps.cisco.com/security/center/softwarechecker.x"] page and follow the instructions. Alternatively, use the following form to determine whether a release is affected by any Cisco Security Advisory. To use the form, follow these steps:
Choose which advisories the tool will search—only this advisory, only advisories with a Critical or High Security Impact Rating (SIR) ["https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html#asr"], or all advisories.
Enter a release number—for example, 15.9(3)M2 or 17.3.3.
Click Check.
Only this advisory All Critical and High advisories All advisories
Vulnerability Policy: To learn about Cisco security vulnerability disclosure policies and publications, see the Security Vulnerability Policy ["http://www.cisco.com/web/about/security/psirt/security_vulnerability_policy.html"]. This document also contains instructions for obtaining fixed software and receiving security vulnerability information from Cisco.
Exploitation and Public Announcements: The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.
Source: This vulnerability was found during the resolution of a Cisco Technical Assistance Center (TAC) support case.
Legal Disclaimer: SOFTWARE DOWNLOADS AND TECHNICAL SUPPORT
The Cisco Support and Downloads ["https://www.cisco.com/c/en/us/support/index.html"] page on Cisco.com provides information about licensing and downloads. This page can also display customer device support coverage for customers who use the My Devices tool. Please note that customers may download only software that was procured from Cisco directly or through a Cisco authorized reseller or partner and for which the license is still valid.
Customers who purchase directly from Cisco but do not hold a Cisco service contract and customers who make purchases through third-party vendors but are unsuccessful in obtaining fixed software through their point of sale should obtain upgrades by contacting the Cisco Technical Assistance Center (TAC) ["https://www.cisco.com/c/en/us/support/web/tsd-cisco-worldwide-contacts.html"]. Customers should have the product serial number available and be prepared to provide the URL of this advisory as evidence of entitlement to a free upgrade.
When considering software upgrades ["https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html#fixes"], customers are advised to regularly consult the advisories ["https://www.cisco.com/go/psirt"] for the relevant Cisco products to determine exposure and a complete upgrade solution. In all cases, customers should ensure that the devices to be upgraded contain sufficient memory and confirm that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, customers are advised to contact the Cisco Technical Assistance Center (TAC) ["https://www.cisco.com/c/en/us/support/web/tsd-cisco-worldwide-contacts.html"] or their contracted maintenance providers.
LEGAL DISCLAIMER DETAILS
CISCO DOES NOT MAKE ANY EXPRESS OR IMPLIED GUARANTEES OR WARRANTIES OF ANY KIND, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. WITHOUT LIMITING THE GENERALITY OF THE FOREGOING, CISCO DOES NOT GUARANTEE THE ACCURACY OR COMPLETENESS OF THIS INFORMATION. THIS DOCUMENT IS PROVIDED ON AN "AS IS" BASIS. YOUR USE OF THE INFORMATION ON THE DOCUMENT OR MATERIALS LINKED FROM THE DOCUMENT IS AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE THIS DOCUMENT AT ANY TIME.
Copies or summaries of the information contained in this Security Advisory may lack important information or contain factual errors. Customers are advised to visit the Cisco Security Advisories ["https://www.cisco.com/go/psirt"] page for the most recent version of this Security Advisory. The Cisco Product Security Incident Response Team (PSIRT) assesses only the affected and fixed release information that is documented in this advisory. See the Cisco Security Vulnerability Policy ["https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html#fixes"] for more information.
8.6 (High)
Vendor Fix
Cisco has released software updates that address this vulnerability.
https://software.cisco.com
References
Acknowledgments
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"text": "A vulnerability in the processing of Control and Provisioning of Wireless Access Points (CAPWAP) packets of Cisco IOS XE Wireless Controller Software for the Catalyst CW9800 Family could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device.\r\n\r\nThis vulnerability is due to improper handling of a malformed CAPWAP packet. An attacker could exploit this vulnerability by sending a malformed CAPWAP packet to an affected device. A successful exploit could allow the attacker to cause the affected device to reload unexpectedly, resulting in a DoS condition.\r\n\r\nCisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.\r\n\r\n\r\n\r\nThis advisory is part of the March 2026 release of the Cisco IOS and IOS XE Software Security Advisory Bundled Publication. For a complete list of the advisories and links to them, see Cisco Event Response: March 2026 Semiannual Cisco IOS and IOS XE Software Security Advisory Bundled Publication [\"https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-75297\"].",
"title": "Summary"
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"title": "Products Confirmed Not Vulnerable"
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"text": "Cisco considers any workarounds and mitigations (if applicable) to be temporary solutions until an upgrade to a fixed software release is available. To fully remediate this vulnerability and avoid future exposure as described in this advisory, Cisco strongly recommends that customers upgrade to the fixed software indicated in this advisory.\r\n Cisco IOS and IOS XE Software\r\nTo help customers determine their exposure to vulnerabilities in Cisco IOS and IOS XE Software, Cisco provides the Cisco Software Checker [\"https://sec.cloudapps.cisco.com/security/center/softwarechecker.x\"]. This tool identifies any Cisco security advisories that impact a specific software release and the earliest release that fixes the vulnerabilities that are described in each advisory (\u201cFirst Fixed\u201d). If applicable, the tool also returns the earliest release that fixes all the vulnerabilities that are described in all the advisories that the Software Checker identifies (\u201cCombined First Fixed\u201d).\r\n\r\nTo use the tool, go to the Cisco Software Checker [\"https://sec.cloudapps.cisco.com/security/center/softwarechecker.x\"] page and follow the instructions. Alternatively, use the following form to determine whether a release is affected by any Cisco Security Advisory. To use the form, follow these steps:\r\n\r\nChoose which advisories the tool will search\u2014only this advisory, only advisories with a Critical or High Security Impact Rating (SIR) [\"https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html#asr\"], or all advisories.\r\nEnter a release number\u2014for example, 15.9(3)M2 or 17.3.3.\r\nClick Check.\r\n\r\n Only this advisory All Critical and High advisories All advisories",
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"text": "This vulnerability was found during the resolution of a Cisco Technical Assistance Center (TAC) support case.",
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"category": "legal_disclaimer",
"text": "SOFTWARE DOWNLOADS AND TECHNICAL SUPPORT\r\n\r\nThe Cisco Support and Downloads [\"https://www.cisco.com/c/en/us/support/index.html\"] page on Cisco.com provides information about licensing and downloads. This page can also display customer device support coverage for customers who use the My Devices tool. Please note that customers may download only software that was procured from Cisco directly or through a Cisco authorized reseller or partner and for which the license is still valid.\r\n\r\nCustomers who purchase directly from Cisco but do not hold a Cisco service contract and customers who make purchases through third-party vendors but are unsuccessful in obtaining fixed software through their point of sale should obtain upgrades by contacting the Cisco Technical Assistance Center (TAC) [\"https://www.cisco.com/c/en/us/support/web/tsd-cisco-worldwide-contacts.html\"]. Customers should have the product serial number available and be prepared to provide the URL of this advisory as evidence of entitlement to a free upgrade.\r\n\r\nWhen considering software upgrades [\"https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html#fixes\"], customers are advised to regularly consult the advisories [\"https://www.cisco.com/go/psirt\"] for the relevant Cisco products to determine exposure and a complete upgrade solution. In all cases, customers should ensure that the devices to be upgraded contain sufficient memory and confirm that current hardware and software configurations will continue to be supported properly by the new release. If the information is not clear, customers are advised to contact the Cisco Technical Assistance Center (TAC) [\"https://www.cisco.com/c/en/us/support/web/tsd-cisco-worldwide-contacts.html\"] or their contracted maintenance providers.\r\n LEGAL DISCLAIMER DETAILS\r\n\r\nCISCO DOES NOT MAKE ANY EXPRESS OR IMPLIED GUARANTEES OR WARRANTIES OF ANY KIND, INCLUDING THE WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR USE. WITHOUT LIMITING THE GENERALITY OF THE FOREGOING, CISCO DOES NOT GUARANTEE THE ACCURACY OR COMPLETENESS OF THIS INFORMATION. THIS DOCUMENT IS PROVIDED ON AN \"AS IS\" BASIS. YOUR USE OF THE INFORMATION ON THE DOCUMENT OR MATERIALS LINKED FROM THE DOCUMENT IS AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE THIS DOCUMENT AT ANY TIME.\r\n\r\nCopies or summaries of the information contained in this Security Advisory may lack important information or contain factual errors. Customers are advised to visit the Cisco Security Advisories [\"https://www.cisco.com/go/psirt\"] page for the most recent version of this Security Advisory. The Cisco Product Security Incident Response Team (PSIRT) assesses only the affected and fixed release information that is documented in this advisory. See the Cisco Security Vulnerability Policy [\"https://sec.cloudapps.cisco.com/security/center/resources/security_vulnerability_policy.html#fixes\"] for more information.",
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"title": "Cisco IOS XE Wireless Controller Software for the Catalyst CW9800 Family CAPWAP Denial of Service Vulnerability",
"tracking": {
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"vulnerabilities": [
{
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"ids": [
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"text": "CSCwp13209"
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],
"notes": [
{
"category": "other",
"text": "Complete.",
"title": "Affected Product Comprehensiveness"
}
],
"product_status": {
"known_affected": [
"CSAFPID-295361",
"CSAFPID-300938",
"CSAFPID-301219",
"CSAFPID-302626",
"CSAFPID-302782",
"CSAFPID-303045",
"CSAFPID-303216",
"CSAFPID-303311",
"CSAFPID-305238",
"CSAFPID-306610",
"CSAFPID-306891"
]
},
"release_date": "2026-03-25T16:00:00+00:00",
"remediations": [
{
"category": "vendor_fix",
"details": "Cisco has released software updates that address this vulnerability.",
"product_ids": [
"CSAFPID-295361",
"CSAFPID-300938",
"CSAFPID-301219",
"CSAFPID-302626",
"CSAFPID-302782",
"CSAFPID-303045",
"CSAFPID-303216",
"CSAFPID-303311",
"CSAFPID-305238",
"CSAFPID-306610",
"CSAFPID-306891"
],
"url": "https://software.cisco.com"
}
],
"scores": [
{
"cvss_v3": {
"baseScore": 8.6,
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H",
"version": "3.1"
},
"products": [
"CSAFPID-295361",
"CSAFPID-300938",
"CSAFPID-301219",
"CSAFPID-302626",
"CSAFPID-302782",
"CSAFPID-303045",
"CSAFPID-303216",
"CSAFPID-303311",
"CSAFPID-305238",
"CSAFPID-306610",
"CSAFPID-306891"
]
}
],
"title": "Cisco IOS XE Software for Wireless LAN Controllers CAPWAP Denial of Service Vulnerbility"
}
]
}
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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