CVE-2026-38891: Gazebo Plugins DoS Vulnerability

CVE-2026-38891 Overview

CVE-2026-38891 is an improper input validation vulnerability [CWE-20] in the gazebo_ros_diff_drive.cpp component of gazebo_plugins v3.9.0. The flaw allows a remote unauthenticated attacker to trigger a Denial of Service (DoS) by supplying a crafted geometry_msgs::Twist message to the affected Robot Operating System (ROS) plugin. Successful exploitation crashes or renders the Gazebo simulation node unresponsive, disrupting robotics simulation workflows that depend on the differential drive plugin. The vulnerability requires no privileges and no user interaction, and the plugin processes messages received over the network via ROS topics.

Critical Impact
A single crafted geometry_msgs::Twist message can crash the gazebo_ros_diff_drive plugin, causing simulation availability loss for connected ROS clients.

Affected Products

gazebo_plugins v3.9.0
gazebo_ros_diff_drive.cpp component
ROS-based robotics simulations that load the affected plugin

Discovery Timeline

2026-07-01 - CVE-2026-38891 published to NVD
2026-07-02 - Last updated in NVD database

Technical Details for CVE-2026-38891

Vulnerability Analysis

The vulnerability resides in gazebo_ros_diff_drive.cpp, a Gazebo plugin that subscribes to geometry_msgs::Twist messages to drive a simulated differential-drive robot. The plugin fails to validate the linear and angular velocity fields carried in incoming Twist messages before consuming them. An attacker publishing a malformed or out-of-range Twist message on the subscribed ROS topic can cause the plugin to abort or the Gazebo simulator process to terminate. This results in loss of availability for the simulation and any downstream consumers that rely on it. The issue is classified as [CWE-20] Improper Input Validation. Public proof-of-concept material demonstrates the crash condition through a video and a written writeup on GitHub.

Root Cause

The plugin trusts incoming ROS message fields without range or sanity checks. Malformed floating-point values or values outside expected physical bounds propagate into physics or actuator computations that assume validated input. The absence of guard conditions on the message handler causes an unrecoverable state in the plugin.

Attack Vector

An attacker with network reachability to the ROS master and topic namespace publishes a crafted geometry_msgs::Twist message to the topic subscribed by gazebo_ros_diff_drive. Because ROS 1 topics accept publishers without authentication by default, no credentials are required. The malformed message is processed by the plugin callback and terminates the simulation node. Refer to the GitHub Documentation for CVE and the GitHub PoC Video for technical detail.

Detection Methods for CVE-2026-38891

Indicators of Compromise

Unexpected termination or crash of the gzserver or Gazebo simulation process shortly after receipt of Twist messages.
ROS log entries showing plugin callback failures within gazebo_ros_diff_drive.
Anomalous publishers appearing on cmd_vel or equivalent Twist topics from untrusted network sources.

Detection Strategies

Monitor ROS topic publishers and flag unauthorized nodes publishing to Twist topics.
Inspect Twist message payloads for NaN, infinity, or values outside plausible velocity ranges.
Correlate simulator process crashes with preceding network traffic to ROS master ports (default TCP 11311) and XML-RPC endpoints.

Monitoring Recommendations

Alert on repeated restarts of the Gazebo simulation service or unexpected exits of gzserver.
Capture and retain ROS network traffic in lab or CI environments to enable retrospective analysis after crashes.
Track exposure of ROS master endpoints on non-loopback interfaces and alert on external connections.

How to Mitigate CVE-2026-38891

Immediate Actions Required

Restrict ROS master and topic exposure to trusted, isolated networks only. Do not expose ROS 1 endpoints to the internet.
Audit which nodes are permitted to publish to Twist topics consumed by gazebo_ros_diff_drive.
Add input validation wrappers or a message filter node that drops Twist messages containing NaN, infinity, or out-of-range values before they reach the plugin.

Patch Information

No vendor patch is referenced in the enriched CVE data at time of publication. Consult the upstream gazebo_plugins repository for updated releases beyond v3.9.0 and monitor project advisories. See the GitHub Documentation for CVE for reproduction details that can guide fix validation.

Workarounds

Deploy the simulation on a segmented network with firewall rules limiting inbound access to the ROS master port.
Insert a sanitizing relay node that republishes only validated Twist messages to the topic consumed by the plugin.
Disable or unload the gazebo_ros_diff_drive plugin in environments where it is not required.

bash

# Configuration example: restrict ROS master to loopback and validate Twist input
export ROS_MASTER_URI=http://127.0.0.1:11311
export ROS_IP=127.0.0.1

# Example: launch a sanitizing relay that filters malformed Twist messages
rosrun topic_tools throttle messages /raw_cmd_vel 50.0 /cmd_vel