CVE-2023-3739 Overview
CVE-2023-3739 affects the Chromad component in Google Chrome on ChromeOS prior to version 115.0.5790.131. The vulnerability stems from insufficient validation of untrusted input, allowing a remote attacker to execute arbitrary code via a crafted shell script. The flaw is categorized under [CWE-77] (Improper Neutralization of Special Elements used in a Command). Google classified the Chromium security severity as Low, while NVD assigned a CVSS 3.1 score of 6.3. User interaction is required for successful exploitation.
Critical Impact
A remote attacker can execute arbitrary code on ChromeOS devices running Chromad by delivering a crafted shell script, requiring user interaction to trigger execution.
Affected Products
- Google Chrome prior to 115.0.5790.131
- Google ChromeOS prior to 115.0.5790.131
- Chromad component on ChromeOS managed enrollments
Discovery Timeline
- 2023-08-01 - CVE-2023-3739 published to NVD
- 2024-11-21 - Last updated in NVD database
Technical Details for CVE-2023-3739
Vulnerability Analysis
The vulnerability resides in Chromad, the ChromeOS component that supports Active Directory enrollment and management. Chromad accepts input that is later interpreted by a shell. Because the component does not adequately validate or neutralize special characters, an attacker can supply a crafted payload that the shell evaluates as commands. The result is arbitrary code execution within the context of the Chromad process. Exploitation requires user interaction, which limits the scope but does not eliminate the threat in managed enterprise environments where ChromeOS devices are widely deployed.
Root Cause
The root cause is improper command neutralization classified as [CWE-77]. Chromad passes attacker-influenced strings into a shell evaluation path without sanitizing metacharacters such as backticks, semicolons, or command substitution syntax. Any externally sourced data that reaches this code path can break out of its intended argument context.
Attack Vector
The attack vector is network-based with low complexity and no privileges required. An attacker delivers a crafted shell script or payload to the target. After the victim interacts with the malicious content, Chromad processes the input and executes the embedded commands. See the Chrome Bug Report #1398986 for technical details.
No verified proof-of-concept code is publicly available for CVE-2023-3739.
The vulnerability is described in prose only; refer to the vendor advisory
for additional technical context.
Detection Methods for CVE-2023-3739
Indicators of Compromise
- Unexpected shell process invocations spawned by Chromad on ChromeOS endpoints.
- Outbound connections from managed ChromeOS devices to unrecognized hosts immediately after policy fetch operations.
- Unsigned or unexpected scripts executing in user or system contexts on enrolled ChromeOS devices.
Detection Strategies
- Inventory ChromeOS device fleets and identify any device running a version earlier than 115.0.5790.131.
- Inspect ChromeOS admin console event logs for anomalous Chromad enrollment or policy actions.
- Correlate user interaction events with subsequent process executions on managed ChromeOS endpoints.
Monitoring Recommendations
- Forward ChromeOS audit logs to a centralized analytics platform for retention and search.
- Alert on unexpected command-line patterns containing shell metacharacters in Chromad-related telemetry.
- Track Chrome and ChromeOS version distribution across the fleet to identify unpatched devices.
How to Mitigate CVE-2023-3739
Immediate Actions Required
- Update all ChromeOS devices to version 115.0.5790.131 or later through the ChromeOS stable channel.
- Verify enforcement of automatic ChromeOS updates via the Google Admin console.
- Restrict installation of untrusted scripts and content on managed ChromeOS endpoints.
Patch Information
Google resolved the issue in the ChromeOS stable channel update referenced in the Google Blog ChromeOS Update. Administrators should confirm devices report version 115.0.5790.131 or higher.
Workarounds
- Limit Chromad usage on devices that cannot be promptly updated by restricting Active Directory enrollment workflows.
- Educate users to avoid executing untrusted shell scripts or content delivered through external channels.
- Apply Google Admin console policies that block unknown extensions and external script sources on ChromeOS.
# Verify ChromeOS version meets the patched baseline
# In chrome://version, confirm the platform string is >= 115.0.5790.131
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
