CVE-2026-2954: Ujcms Ujcms RCE Vulnerability Explained

CVE-2026-2954 Overview

A critical injection vulnerability has been identified in Dromara UJCMS version 10.0.2. The vulnerability exists within the importChanel function located in the /api/backend/ext/import-data/import-channel endpoint of the ImportDataController component. Attackers can exploit this flaw by manipulating the driverClassName and url arguments, enabling injection attacks that can be initiated remotely over the network.

The exploit has been publicly disclosed, increasing the risk of active exploitation. Notably, the vendor was contacted regarding this vulnerability but did not respond, leaving users without an official patch or mitigation guidance.

Critical Impact

Remote attackers with low privileges can exploit this injection vulnerability to manipulate database driver configurations, potentially leading to unauthorized data access, data manipulation, or further system compromise through JDBC connection string injection.

Affected Products

• Dromara UJCMS version 10.0.2
• UJCMS installations with ImportDataController component enabled
• Systems exposing the /api/backend/ext/import-data/import-channel endpoint

Discovery Timeline

• 2026-02-22 - CVE-2026-2954 published to NVD
• 2026-02-25 - Last updated in NVD database

Technical Details for CVE-2026-2954

Vulnerability Analysis

This vulnerability falls under CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component), commonly known as an Injection vulnerability. The flaw resides in the importChanel function within the ImportDataController, which handles data import operations through the /api/backend/ext/import-data/import-channel API endpoint.

The vulnerability arises from insufficient validation and sanitization of user-supplied input in the driverClassName and url parameters. These parameters are used to configure database connections during the import process. An attacker with low-level privileges can craft malicious values that get injected into the database connection configuration, potentially allowing them to:

• Specify arbitrary JDBC drivers for execution
• Inject malicious connection strings that redirect database operations
• Potentially achieve code execution through JDBC driver exploitation techniques

The attack can be initiated remotely over the network, requiring only basic authentication. The impact includes partial compromise of confidentiality, integrity, and availability of the affected system.

Root Cause

The root cause of CVE-2026-2954 is improper input validation in the ImportDataController's importChanel function. The application fails to adequately sanitize or validate the driverClassName and url parameters before using them in database connection configurations. This allows attackers to inject arbitrary values that are processed by the downstream JDBC connection handling logic, violating the principle of secure input handling and enabling injection attacks.

Attack Vector

The attack is conducted remotely over the network against the /api/backend/ext/import-data/import-channel API endpoint. An authenticated attacker with low privileges can send specially crafted HTTP requests containing malicious values in the driverClassName or url parameters.

The vulnerability does not require user interaction and can be exploited with low attack complexity. By manipulating the JDBC driver class name or connection URL, attackers can potentially force the application to load arbitrary JDBC drivers or connect to attacker-controlled databases, leading to various exploitation scenarios including data exfiltration or remote code execution through malicious JDBC drivers.

For technical details regarding the exploitation mechanism, refer to the Yuque Security Document or the VulDB entry.

Detection Methods for CVE-2026-2954

Indicators of Compromise

• Unusual HTTP POST requests to /api/backend/ext/import-data/import-channel endpoint with suspicious driverClassName or url parameter values
• Attempted loading of non-standard or unexpected JDBC drivers in application logs
• Database connection attempts to external or unauthorized hosts
• Presence of unexpected JAR files or class loaders in the application runtime

Detection Strategies

• Implement web application firewall (WAF) rules to inspect and filter requests to the /api/backend/ext/import-data/import-channel endpoint for injection patterns
• Monitor application logs for anomalous import channel operations or database driver loading attempts
• Deploy endpoint detection and response (EDR) solutions to identify suspicious Java process behavior
• Create SIEM correlation rules to detect multiple failed or suspicious API calls to the import-data endpoints

Monitoring Recommendations

• Enable detailed logging for the ImportDataController component and all database connection operations
• Monitor for outbound network connections from the UJCMS application to unexpected external databases
• Track authentication events followed by immediate access to the import-data API endpoints
• Implement anomaly detection for database configuration changes or driver loading events

How to Mitigate CVE-2026-2954

Immediate Actions Required

• Restrict access to the /api/backend/ext/import-data/import-channel endpoint to only trusted administrators
• Implement network-level controls to limit access to the UJCMS backend API
• Deploy a web application firewall with rules to block injection attempts in the driverClassName and url parameters
• Consider temporarily disabling the import-data functionality if not critical to operations
• Review access logs for any signs of prior exploitation attempts

Patch Information

At the time of publication, no official patch has been released by the vendor. According to the vulnerability disclosure, the vendor (Dromara/UJCMS) was contacted regarding this vulnerability but did not respond. Organizations using UJCMS 10.0.2 should monitor the VulDB entry and official UJCMS channels for future security updates.

Workarounds

• Implement strict input validation at the network perimeter using WAF rules to whitelist only approved JDBC driver class names
• Restrict the import-data API endpoint to internal network access only using firewall rules or reverse proxy configurations
• Apply principle of least privilege by limiting which user accounts have access to the data import functionality
• Consider deploying application-level input validation middleware to sanitize the driverClassName and url parameters before they reach the vulnerable function

# Example: Restrict access to vulnerable endpoint using nginx
location /api/backend/ext/import-data/ {
    # Allow only from trusted admin IP ranges
    allow 10.0.0.0/8;
    allow 192.168.1.0/24;
    deny all;
    
    # Additional rate limiting
    limit_req zone=import_api burst=5 nodelay;
}