Summary

• A vulnerability in the web-based management interface of Cisco Small Business RV016, RV042, RV042G, RV082, RV320, and RV325 Routers could allow an authenticated, remote attacker to execute arbitrary commands on an affected device.

  This vulnerability is due to improper validation of user input within incoming HTTP packets. An attacker could exploit this vulnerability by sending a crafted HTTP request to the web-based management interface. A successful exploit could allow the attacker to gain root-level privileges and access unauthorized data. To exploit this vulnerability, an attacker would need to have valid administrative credentials on the affected device.

  Cisco has not released software updates that address this vulnerability. There are no workarounds that address this vulnerability. However, administrators may disable the affected feature as described in the Workarounds section.

  This advisory is available at the following link:
  https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sb-rv01x_rv32x_rce-nzAGWWDD

Affected Products

• Vulnerable Products

  At the time of publication, this vulnerability affected the following Cisco RV Series Small Business Routers:

  • RV016 Multi-WAN VPN Routers
  • RV042 Dual WAN VPN Routers
  • RV042G Dual Gigabit WAN VPN Routers
  • RV082 Dual WAN VPN Routers
  • RV320 Dual Gigabit WAN VPN Routers
  • RV325 Dual Gigabit WAN VPN Routers

   

  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 RV Series Small Business Routers:

  • RV160 VPN Routers
  • RV160W Wireless-AC VPN Routers
  • RV260 VPN Routers
  • RV260P VPN Routers with PoE
  • RV260W Wireless-AC VPN Routers
  • RV340 Dual WAN Gigabit VPN Routers
  • RV340W Dual WAN Gigabit Wireless-AC VPN Routers
  • RV345 Dual WAN Gigabit VPN Routers
  • RV345P Dual WAN Gigabit PoE VPN Routers

Workarounds

• There are no workarounds that address this vulnerability. 

  To mitigate this vulnerability on Cisco Small Business RV320 and RV325 Routers, disable remote management. To mitigate this vulnerability on Cisco Small Business RV016, RV042, RV042G, and RV082 Routers, disable remote management and block access to ports 443 and 60443. The routers will still be accessible through the LAN interface after the mitigation has been implemented.

  Disable Remote Management

  To disable remote management, do the following:

  1. Log in to the web-based management interface for the device.
  2. Choose Firewall > General.
  3. Uncheck the Remote Management check box.

  Block Access to Ports 443 and 60443

  First, add a new service to the access rules of the device for port 60443. It is not necessary to create a service for port 443 because it is predefined in the services list.

  1. Log in to the web-based management interface for the device.
  2. Choose Firewall > Access Rules.
  3. Click Service Management.
  4. In the Service Name field, enter TCP-60443.
  5. From the Protocol drop-down list, choose TCP.
  6. In both of the Port Range fields, enter 60443.
  7. Click Add to List.
  8. Click OK.

  Next, create access rules to block ports 443 and 60443. To create an access rule to block port 443, do the following:

  1. Log in to the web-based management interface for the device.
  2. Choose Firewall > Access Rules.
  3. Click Add.
  4. From the Action drop-down list, choose Deny.
  5. From the Service drop-down list, choose HTTPS (TCP 443-443).
  6. From the Log drop-down list, choose Log packets match this rule.
  7. From the Source Interface drop-down list, choose the option that matches the WAN connection on the device.
  8. From the Source IP drop-down list, choose Any.
  9. From the Destination IP drop-down list, choose Single.
  10. In both of the Destination IP fields, enter the WAN IP address.
  11. Click Save.

  To create an access rule to block port 60443, repeat the preceding steps, but for Step 5, choose HTTPS (TCP 60443-60443) from the Service drop-down list.

  Note: If a second WAN port is being used, two additional ACL rules need to be set up using the WAN number and IP address for the second WAN port.

  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 not released and will not release software updates to address the vulnerability described in this advisory. Cisco Small Business RV016, RV042, RV042G, RV082, RV320 and RV325 Routers have entered the end-of-life process. Customers are advised to refer to the end-of-life notices for these products:

  End-of-Sale and End-of-Life Announcement for the Cisco RV016 Multi-WAN VPN Router
  End-of-Sale and End-of-Life Announcement for the Cisco RV042 and RV042G VPN Router (all models)
  End-of-Sale and End-of-Life Announcement for the Cisco RV082 Dual WAN VPN Router
  End-of-Sale and End-of-Life Announcement for the Cisco RV320 and RV325 Dual Gigabit WAN VPN Router

  When considering a device migration, 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 new products will be sufficient for their network needs, that the new devices contain sufficient memory, and that current hardware and software configurations will continue to be supported properly by the new product. If the information is not clear, customers are advised to contact the Cisco Technical Assistance Center (TAC) or their contracted maintenance providers.

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

• Cisco would like to thank FeiXincheng and ShaLetian of X1cT34m for reporting this vulnerability.

URL

• https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sb-rv01x_rv32x_rce-nzAGWWDD

Revision History

• Version	Description	Section	Status	Date
  1.1	Updated the workarounds section.	Workarounds	Final	2023-APR-05
  1.0	Initial public release.	—	Final	2023-APR-05

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