Summary

• A vulnerability in the request authentication validation for the REST API of Cisco SD-WAN vManage software could allow an unauthenticated, remote attacker to gain read permissions or limited write permissions to the configuration of an affected Cisco SD-WAN vManage instance.

  This vulnerability is due to insufficient request validation when using the REST API feature. An attacker could exploit this vulnerability by sending a crafted API request to an affected vManage instance. A successful exploit could allow the attacker to retrieve information from and send information to the configuration of the affected Cisco vManage instance. This vulnerability only affects the REST API and does not affect the web-based management interface or the CLI.

  Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

  This advisory is available at the following link:
  https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-vmanage-unauthapi-sphCLYPA

Affected Products

• Vulnerable Products

  This vulnerability affects vulnerable releases of Cisco SD-WAN vManage software.

  For information about which Cisco software releases are vulnerable, see the Fixed Software section of this advisory.

  Products Confirmed Not Vulnerable

  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:

  • IOS XE
  • IOS XE SD-WAN
  • SD-WAN cEdge Routers
  • SD-WAN vBond Orchestrator Software
  • SD-WAN vEdge Cloud Routers
  • SD-WAN vEdge Routers
  • SD-WAN vSmart Controller Software

Details

• Cisco SD-WAN vManage API is a REST API for controlling, configuring, and monitoring the Cisco devices in an overlay network. Use cases for the vManage API include the following:

  • Monitoring device status
  • Configuring a device, such as attaching a template to a device
  • Querying and aggregating device statistics

  Customers may be able to detect attempts to access the REST API by examining the log file. The REST API log file is located at the following path in the vManage filesystem: /var/log/nms/vmanage-server.log.

  Administrators can use the CLI command show log, as in the following example, to view the content of the vmanage-server.log file:

  vmanage# show log /var/log/nms/vmanage-server.log

  If Request Stored in Map is (/dataservice/client/server) for user (admin) appears in the log, the REST API has received requests:

  30-Jun-2023 15:17:03,888 UTC INFO  [ST3_vmanage1] [AppServerLoginModule] (default task-202) |default| Localization: Locale value after setting for non-SAML User upon login: null
  30-Jun-2023 15:17:03,930 UTC INFO  [ST3_vmanage1] [UserUtils] (default task-202) |default| Request Stored in Map is (/dataservice/client/server) for user (admin)
  30-Jun-2023 15:17:03,933 UTC INFO  [ST3_vmanage1] [UserUtils] (default task-202) |default| localUserFile : /etc/viptela/aaa_auth_grp/admin, radiusUserFile : /etc/viptela/aaa_auth_grp/admin.external
  30-Jun-2023 15:17:03,933 UTC INFO  [ST3_vmanage1] [UserUtils] (default task-202) |default| localUserFile exists : false, isFile : false

  However, customers must perform their own impact analysis based on the information in the log and any user accounts configured on the vManage. The preceding log output is an example only, for customer reference. User account requests that are seen in this log may vary depending on the configuration of the user accounts within customers' vManage instance.

  NOTE: The presence of requests in this log does not indicate unauthorized access; rather, it only indicates that attempts have been made to access the REST API.

  Cisco continues to recommend that customers use API keys to access APIs, as documented in the Cisco SD-WAN vManage Documentation.

Workarounds

• There are no workarounds that address this vulnerability. However, to mitigate this vulnerability and significantly reduce the attack surface, network administrators should enable access control lists (ACLs) to limit access to the vManage instance.

  In cloud hosted deployments, access to vManage is limited by ACLs that contain permitted IP addresses. Network administrators should review and edit the permitted IP addresses in the ACLs. In on-premises deployments, vManage access can be limited in a similar way by using ACLs and configuring permitted IP addresses.

  While this mitigation has been deployed and was proven successful in a test environment, customers should determine the applicability and effectiveness in their own environment and under their own use conditions. Customers should be aware that any workaround or mitigation that is implemented may negatively impact the functionality or performance of their network based on intrinsic customer deployment scenarios and limitations. Customers should not deploy any workarounds or mitigations before first evaluating the applicability to their own environment and any impact to such environment.

Fixed Software

• Cisco has released free software updates that address the vulnerability described in this advisory. Customers with service contracts that entitle them to regular software updates should obtain security fixes through their usual update channels.

  Customers may only install and expect support for software versions and feature sets for which they have purchased a license. By installing, downloading, accessing, or otherwise using such software upgrades, customers agree to follow the terms of the Cisco software license:
  https://www.cisco.com/c/en/us/products/end-user-license-agreement.html

  Additionally, customers may only download software for which they have a valid license, procured from Cisco directly, or through a Cisco authorized reseller or partner. In most cases this will be a maintenance upgrade to software that was previously purchased. Free security software updates do not entitle customers to a new software license, additional software feature sets, or major revision upgrades.

  The Cisco Support and Downloads 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.

  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.

  Customers Without Service Contracts

  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 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.

  Fixed Releases

  Customers are advised to upgrade to an appropriate fixed software release as indicated in the following table(s):

  Cisco SD-WAN vManage Release	First Fixed Release
  18.3	Not affected.
  18.4	Not affected.
  19.1	Not affected.
  19.2	Not affected.
  20.1	Not affected.
  20.3	Not affected.
  20.4	Not affected.
  20.5	Not affected.
  20.6.1	Not affected.
  20.6.2	Not affected.
  20.6.3	Not affected.
  20.6.3.1	Not affected.
  20.6.3.2	Not affected.
  20.6.3.3	20.6.3.4
  20.6.4	20.6.4.2
  20.6.5	20.6.5.5
  20.7	Migrate to a fixed release.
  20.8	Migrate to a fixed release.
  20.9	20.9.3.2
  20.10	20.10.1.2
  20.11	20.11.1.2

  The Cisco Product Security Incident Response Team (PSIRT) validates only the affected and fixed release information that is documented in this advisory.

Exploitation and Public Announcements

• The Cisco PSIRT is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory.

Source

• Cisco would like to thank Nicholas Buckingham of Verizon for reporting this vulnerability.

URL

• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-vmanage-unauthapi-sphCLYPA

Revision History

• Version	Description	Section	Status	Date
  1.2	Updated source.	Source	Final	2024-MAR-12
  1.1	Updated REST API log output information and fixed release information for Release 20.6.3	Details and Fixed Releases	Final	2023-JUL-12
  1.0	Initial public release.	-	Final	2023-JUL-12

  Show Less