CVE-2019-1653: Cisco Small Business RV320 and RV325 Routers Information Disclosure Vulnerability

CVE-2019-1653 is an information disclosure vulnerability in Cisco Small Business RV320 and RV325 Dual Gigabit WAN VPN Routers. Improper access controls on certain URLs can let an attacker obtain the router configuration or detailed diagnostic information. That material often includes credentials, VPN settings, and network topology details that can enable further compromise of the device or the networks behind it. IT and security teams should treat exposed management interfaces on these models as high priority until they confirm the vendor fix is applied.

How it works

The weakness is classified as CWE-284 (Improper Access Control). On the affected routers, certain URLs that serve configuration or diagnostic data do not enforce adequate access restrictions. An unauthenticated or insufficiently authorized remote attacker who can reach those URLs may retrieve the full configuration file or diagnostic output. Configuration dumps commonly contain plaintext or reversible credentials, pre-shared keys, firewall rules, and routing information. Once obtained, that data can be used to authenticate to the device, pivot into internal networks, or plan follow-on attacks. Exact request paths and any authentication bypass details must be confirmed against the vendor advisory; do not rely on third-party write-ups alone.

Am I affected? How to find it in your systems

These devices are Cisco Small Business RV320 and RV325 routers, typically deployed at branch offices, small businesses, or remote sites as dual-WAN VPN edge routers. They often sit at the perimeter with WAN interfaces reachable from the internet and LAN/VPN interfaces facing internal networks.

• Inventory: Query asset management, network discovery, or configuration-management databases for model strings “RV320” and “RV325”. Check DHCP/ARP tables, CDP/LLDP neighbors, and firewall object groups that reference these hostnames or management IPs.
• Version and exposure check: Log into each device’s web UI or use SNMP/CLI to record the running firmware. Confirm whether the management interface (HTTP/HTTPS) or any diagnostic endpoints are reachable from untrusted networks. Compare the installed release against the fixed versions listed in the Cisco advisory for CVE-2019-1653.
• Telemetry signs: Look for unusual GET requests to configuration or diagnostic URLs in web-server or reverse-proxy logs, especially from external source IPs. Alert on sudden downloads of large text or binary files from the router, unexpected configuration exports, or repeated access attempts to management paths that normally require authentication. Packet captures or NetFlow showing connections to the device’s HTTPS/HTTP ports from the internet warrant investigation.

If you cannot determine the exact firmware level, assume the device is vulnerable until proven otherwise by the vendor’s fixed-release list.

How to remediate

Patch first. Apply the firmware updates published by Cisco for the RV320 and RV325 that address CVE-2019-1653, following the vendor’s installation instructions and any prerequisite steps. After upgrading, verify the new version string and reboot if required. CISA directs organizations to apply updates per vendor instructions.

• Restrict management access immediately after patching: bind the web UI to an internal or management-only interface, require HTTPS, and enforce strong authentication.
• Rotate any credentials, VPN pre-shared keys, or certificates that may have been present in prior configuration exports.
• Disable unnecessary services and URL handlers if the vendor documentation allows it.
• Document the change and re-scan the device from an external perspective to confirm the previously exposed endpoints no longer return configuration data.

If you can't patch immediately

Implement compensating controls while you schedule the firmware update:

• Network segmentation: Place the router’s management interface behind a firewall or ACL that permits access only from a jump host or dedicated management subnet. Block WAN-side access to HTTP/HTTPS management ports entirely if operationally feasible.
• Virtual patching / WAF: If a reverse proxy or web-application firewall sits in front of the device, add rules that deny requests to known configuration and diagnostic URL patterns. Confirm patterns against the vendor advisory rather than guessing.
• Feature disablement: Turn off remote management, diagnostic export functions, or any guest/admin URL access that is not required.
• Heightened monitoring: Enable and forward web-access and system logs to a SIEM; alert on any successful or attempted retrieval of configuration files. Increase frequency of configuration-integrity checks.
• Credential hygiene: Treat all secrets stored on the device as potentially exposed; prepare to rotate them as soon as patching is complete.

These measures reduce risk but do not replace the vendor fix.

If your data may have been exposed

Actively exploited information-disclosure flaws on edge routers frequently lead to credential theft and broader network breaches. If logs or external scanning indicate that configuration or diagnostic data left the device, assume secrets are compromised: rotate passwords, VPN keys, and certificates, and review downstream systems for unauthorized access. You can run a free exposure scan of your email addresses to check whether they appear in known breach data sets and take additional account-protection steps as needed.