On October 10, 2023, the following HTTP/2 protocol-level weakness, which enables a novel distributed denial of service (DDoS) attack technique, was disclosed: CVE-2023-44487: HTTP/2 Rapid Reset For a description of this vulnerability, see the following publications: How it works: The novel HTTP/2 'Rapid Reset' DDoS attack (Google) HTTP/2 Zero-Day vulnerability results in record-breaking DDoS attacks (Cloudflare) CVE-2023-44487 - HTTP/2 Rapid Reset Attack (AWS) This advisory will be updated as additional information becomes available. This advisory is available at the following link:https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-http2-reset-d8Kf32vZ
On October 10, 2023, the following HTTP/2 protocol-level weakness, which enables a novel distributed denial of service (DDoS) attack technique, was disclosed:
CVE-2023-44487: HTTP/2 Rapid Reset
For a description of this vulnerability, see the following publications:
This advisory will be updated as additional information becomes available.
This advisory is available at the following link:
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-http2-reset-d8Kf32vZ
Cisco is investigating its product line to determine which products may be affected by this vulnerability and the impact on each affected product. As the investigation progresses, Cisco will update this advisory with information about affected products.
The Vulnerable Products section will include Cisco bug IDs for each affected product. The bugs are accessible through the Cisco Bug Search Tool and contain additional platform-specific information, including workarounds (if available) and fixed software releases.
No Cisco cloud-based offering is currently known to be affected. As the investigation progresses, Cisco will remediate impact on any cloud-based offerings if required.
The following table lists Cisco products that are affected by the vulnerability that is described in this advisory. If a future release date is indicated for software, the date provided represents an estimate based on all information known to Cisco as of the Last Updated date at the top of the advisory. Availability dates are subject to change based on a number of factors, including satisfactory testing results and delivery of other priority features and fixes. If no version or date is listed for an affected component (indicated by a blank field and/or an advisory designation of Interim), Cisco is continuing to evaluate the fix and will update the advisory as additional information becomes available. After the advisory is marked Final, customers should refer to the associated Cisco bug(s) for further details.
| Product | Cisco Bug ID | Fixed Release Availability |
|---|---|---|
| Network and Content Security Devices | ||
| Secure Dynamic Attribute Connector (CSDAC) | CSCwh89890 | 2.2 (Nov 2023) 2.3 (Nov 2023) |
| Secure Malware Analytics Appliance, formerly Threat Grid Appliance | CSCwh88721 | 2.19.2 (Dec 2023) |
| Network Management and Provisioning | ||
| Business Process Automation | CSCwh88580 | 3.2.003.009 (Nov 2023) 4.0.001.003 (Nov 2023) 4.0.002.003 (Nov 2023) |
| Crosswork Data Gateway | CSCwh88729 | 4.1.3 (Dec 2023) 5.0.2 (Dec 2023) 6.0 (Dec 2023) |
| Crosswork Situation Manager (when HTTP/2 is enabled, it's disabled by default) | CSCwh88658 | Contact Cisco TAC for upgrade options |
| Crosswork Zero Touch Provisioning (ZTP) | CSCwh88727 | 6.0.0 (Dec 2023) |
| Data Center Network Manager (DCNM) - SAN Deployments on Windows or Linux | CSCwh88607 | Apply Workaround |
| IoT Field Network Director, formerly Connected Grid Network Management System | CSCwh88604 | 4.11.0 (Dec 2023) |
| Prime Access Registrar | CSCwh88632 | 9.3.3 (Feb 2024) |
| Prime Cable Provisioning | CSCwh91177 | 7.2.1 (Nov 2023) |
| Prime Infrastructure | CSCwh84581 | 3.10.4 (Dec 2023) |
| Prime Network Registrar | CSCwh88631 | 11.2 (Available) |
| Routing and Switching - Enterprise and Service Provider | ||
| IOx Fog Director | CSCwh89927 | 1.22 (Nov 2023) |
| Nexus 3000 Series Switches | CSCwh88614 | |
| Nexus 9000 Series Switches in standalone NX-OS mode | CSCwh88614 | |
| Ultra Cloud Core - Access and Mobility Management Function | CSCwh88572 | 2024.02.0 (May 2024) |
| Ultra Cloud Core - Policy Control Function | CSCwh88574 | 2024.01.0 (Feb 2024) |
| Ultra Cloud Core - Session Management Function | CSCwh88576 | |
| Voice and Unified Communications Devices | ||
| Enterprise Chat and Email | CSCwh88749 | Apply Microsoft Windows Update or Workaround |
| Unified Attendant Console Advanced | CSCwh88736 | Apply Microsoft Windows Update or Workaround |
| Unified Contact Center Domain Manager (CCDM) | CSCwh88737 | Apply Microsoft Windows Update or Workaround |
| Unified Contact Center Enterprise (UCCE) | CSCwh88584 | Apply Microsoft Windows Update or Workaround |
| Unified Contact Center Enterprise - Live Data server | CSCwh88583 | 12.6.2 (Nov 2023) |
| Unified Contact Center Express (UCCX) | CSCwh88746 | |
| Unified Contact Center Management Portal (CCMP) | CSCwh88737 | Apply Microsoft Windows Update or Workaround |
| Video, Streaming, TelePresence, and Transcoding Devices | ||
| Expressway Series | CSCwh88665 | X14.3.3 (Dec 2023) |
| TelePresence Video Communication Server (VCS) | CSCwh88665 | X14.3.3 (Dec 2023) |
| Wireless | ||
| Connected Mobile Experiences | CSCwh89894 | 11.1 (Feb 2024) |
Only products listed in the Vulnerable Products 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:
Cable Devices
Collaboration and Social Media
Endpoint Clients and Client Software
Meraki Products
Network Application, Service, and Acceleration
Network and Content Security Devices
Network Management and Provisioning
Routing and Switching - Enterprise and Service Provider
Routing and Switching - Small Business
Unified Computing
Voice and Unified Communications Devices
Video, Streaming, TelePresence, and Transcoding Devices
Wireless
For potential workarounds on a specific Cisco product, refer to the Cisco bug ID, available from the Cisco Bug Search Tool.
For information about fixed software releases, consult the Cisco bugs identified in the Vulnerable Products section of this advisory.
When considering software upgrades, customers are advised to regularly consult the advisories for Cisco products, which are available from the Cisco Security Advisories page, 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) or their contracted maintenance providers.
The Cisco Product Security Incident Response Team (PSIRT) is aware of attempted exploitation of this vulnerability in the wild.
This vulnerability was publicly disclosed by Google, Cloudflare, and AWS on October 10, 2023.
To learn about Cisco security vulnerability disclosure policies and publications, see the Security Vulnerability Policy. This document also contains instructions for obtaining fixed software and receiving security vulnerability information from Cisco.
| Version | Description | Section | Status | Date |
|---|---|---|---|---|
| 1.8 | Updated the lists of vulnerable products and products confirmed not vulnerable. | Vulnerable Products and Products Confirmed Not Vulnerable | Interim | 2023-NOV-09 |
| 1.7 | Updated the lists of vulnerable products and products confirmed not vulnerable and fixed releases availability. | Vulnerable Products and Products Confirmed Not Vulnerable | Interim | 2023-NOV-02 |
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