CVE-2024-20470: Cisco RV340 VPN Router RCE Vulnerability

CVE-2024-20470 Overview

CVE-2024-20470 is an authenticated remote code execution vulnerability affecting the web-based management interface of Cisco Small Business RV340, RV340W, RV345, and RV345P Dual WAN Gigabit VPN Routers. The flaw stems from insufficient validation of user-supplied input in HTTP requests processed by the management interface. An authenticated attacker with valid admin credentials can send crafted HTTP input to execute arbitrary code as the root user on the underlying operating system. Cisco has confirmed that these end-of-life devices will not receive a patch, leaving migration to supported platforms as the only remediation path.

Critical Impact
Successful exploitation yields arbitrary code execution as root on the router, giving attackers full control over the device, network traffic, and any VPN tunnels it terminates.

Affected Products

Cisco Small Business RV340 Dual WAN Gigabit VPN Router (firmware versions 1.0.00.29 through 1.0.03.29)
Cisco Small Business RV340W Dual WAN Gigabit Wireless-AC VPN Router (firmware versions 1.0.00.29 through 1.0.03.29)
Cisco Small Business RV345 and RV345P Dual WAN Gigabit VPN Routers (firmware versions 1.0.00.29 through 1.0.03.29)

Discovery Timeline

2024-10-02 - CVE-2024-20470 published to NVD with Cisco security advisory cisco-sa-rv34x-privesc-rce-qE33TCms
2026-06-17 - Last updated in NVD database

Technical Details for CVE-2024-20470

Vulnerability Analysis

The vulnerability is classified under [CWE-146] (Improper Neutralization of Expression/Command Delimiters) and results in arbitrary code execution on the router's underlying Linux operating system. The web-based management interface accepts user-supplied input in HTTP request parameters without adequate sanitization or validation. When this untrusted input reaches a downstream execution context, an attacker can break out of the intended data boundaries and inject operating system commands or code that the router process executes.

Because the vulnerable web management daemon runs with root privileges, successful exploitation grants complete control of the device. Attackers can modify routing tables, capture VPN traffic, pivot into internal networks, or install persistent implants in firmware. Exploitation requires valid admin credentials, which reduces the population of potential attackers but does not mitigate the risk from credential theft, brute force against exposed management interfaces, or malicious insiders.

Root Cause

The web management interface fails to sufficiently validate user-supplied input before passing it to lower-level system routines. The improper handling of delimiter characters in HTTP request parameters allows crafted values to alter the intended structure of downstream operations, producing unintended command or code execution on the router's operating system.

Attack Vector

Exploitation occurs over the network against the router's web management interface. The attacker authenticates using valid administrator credentials, then submits a crafted HTTP request containing malicious input to a vulnerable endpoint. The malformed input traverses the input-validation logic and reaches an execution sink, causing the router to run attacker-supplied code as root.

// No public proof-of-concept code is available for CVE-2024-20470.
// Refer to the Cisco Security Advisory (cisco-sa-rv34x-privesc-rce-qE33TCms)
// for authoritative technical details.

Detection Methods for CVE-2024-20470

Indicators of Compromise

Unexpected administrator logins to the RV340/RV345 web management interface from unusual source IP addresses or outside business hours.
New or modified processes running as root on the router that do not correspond to standard Cisco firmware components.
Outbound connections from the router to unknown external hosts, particularly to command-and-control style endpoints.
Unexplained changes to routing tables, firewall rules, or VPN configuration on affected devices.

Detection Strategies

Monitor authentication logs from RV340, RV340W, RV345, and RV345P devices for successful admin logins followed by configuration changes or reboots.
Inspect HTTP request logs for anomalous parameter values containing shell metacharacters, command delimiters, or unusually long strings targeting management endpoints.
Baseline expected administrative traffic patterns and alert on deviations, including access from geographies or subnets that should not manage the device.

Monitoring Recommendations

Forward syslog and HTTP access telemetry from affected routers to a centralized SIEM or data lake for correlation with endpoint and identity events.
Alert on any web management interface exposure to the public internet using external attack surface scans.
Track firmware version and configuration drift across all Cisco Small Business routers to identify unauthorized changes.

How to Mitigate CVE-2024-20470

Immediate Actions Required

Restrict access to the router web management interface to a trusted management VLAN or jump host, and block WAN-side access entirely.
Rotate all administrator credentials on affected RV340, RV340W, RV345, and RV345P devices and enforce strong, unique passwords.
Audit administrator accounts and remove any that are unused, shared, or unnecessary.
Plan migration to a currently supported Cisco routing platform, since the affected RV Series devices have entered the end-of-life process.

Patch Information

According to the Cisco Security Advisory, Cisco has not released and will not release firmware updates to address CVE-2024-20470 for the RV340, RV340W, RV345, and RV345P routers because these products have passed end-of-software-maintenance milestones. Customers should migrate to a supported product family. No workaround eliminates the vulnerability on affected devices.

Workarounds

Disable remote management on the WAN interface so the web-based management interface is not reachable from untrusted networks.
Place the router's management interface behind a firewall that permits access only from a hardened administrator workstation or bastion.
Enforce multi-factor authentication on any identity provider or jump host used to reach the router management network to reduce the risk of credential compromise.

bash

# Example: restrict web management access to a trusted subnet only
# Log in to the RV34x web UI and configure:
#   Firewall > Access Rules > Add
#     Action: Deny
#     Service: HTTPS
#     Source: ANY
#     Destination: WAN interface
#   Firewall > Access Rules > Add
#     Action: Allow
#     Service: HTTPS
#     Source: <trusted-management-subnet>/24
#     Destination: LAN interface
# Then disable Remote Web Management under
#   Firewall > Basic Settings > Remote Web Management: Off