CVE-2025-11903: Chancms Chancms SQL Injection Vulnerability

CVE-2025-11903 Overview

CVE-2025-11903 is a SQL injection vulnerability in yanyutao0402 ChanCMS versions up to 3.3.2. The flaw resides in the update function of the /cms/article/update endpoint. Attackers can manipulate the cid argument to inject arbitrary SQL statements into backend database queries. The issue requires low privileges and can be exploited remotely over the network without user interaction. The vendor was contacted prior to public disclosure but did not respond. A public exploit has been referenced through VulDB, increasing the risk of opportunistic exploitation against exposed ChanCMS instances.

Critical Impact
Authenticated remote attackers can manipulate database queries through the cid parameter, potentially exposing or modifying article data stored in ChanCMS deployments.

Affected Products

yanyutao0402 ChanCMS versions up to and including 3.3.2
ChanCMS /cms/article/update endpoint
Deployments exposing the article management interface to authenticated users

Discovery Timeline

2025-10-17 - CVE-2025-11903 published to the National Vulnerability Database (NVD)
2026-04-29 - Last updated in NVD database

Technical Details for CVE-2025-11903

Vulnerability Analysis

The vulnerability is classified under [CWE-89] (Improper Neutralization of Special Elements used in an SQL Command) and [CWE-74] (Improper Neutralization of Special Elements in Output Used by a Downstream Component). The defect lives in the update function handling requests to /cms/article/update within ChanCMS. The application accepts the cid parameter from the client and concatenates it into a SQL statement without proper sanitization or parameterization. An authenticated attacker can supply crafted input that alters query logic, enabling unauthorized data retrieval or modification within the underlying database. EPSS data reports a probability of 0.034% at the 10.363 percentile, indicating low observed exploitation activity, but a published exploit reference exists in VulDB submission #670271.

Root Cause

The root cause is missing input validation and lack of prepared statements in the update function of the article controller. User-controlled values flow directly into dynamic SQL construction, allowing query manipulation through the cid argument.

Attack Vector

An authenticated remote attacker sends a crafted HTTP request to /cms/article/update with malicious SQL payloads in the cid parameter. Because the attack requires only low privileges and no user interaction, any account with access to the article update functionality can trigger the flaw. See the GitHub Vulnerability Discovery Note for technical details of the affected request path.

Detection Methods for CVE-2025-11903

Indicators of Compromise

HTTP POST requests targeting /cms/article/update containing SQL meta-characters such as ', --, UNION, or SLEEP( in the cid parameter
Anomalous response times or 500-series errors originating from the ChanCMS article update endpoint
Unexpected modifications to article records or database error log entries referencing the cid field

Detection Strategies

Deploy web application firewall (WAF) rules that flag SQL injection patterns in the cid parameter of /cms/article/update
Enable database query logging and alert on syntactically unusual statements originating from the ChanCMS application user
Correlate authentication logs with article-update activity to identify low-privilege accounts performing unexpected administrative actions

Monitoring Recommendations

Monitor outbound traffic from the database server for signs of data exfiltration triggered by injected queries
Track failed and successful logins to ChanCMS administrative interfaces and review session activity for low-privilege accounts
Review reverse proxy and application logs for repeated requests to /cms/article/update from a single source

How to Mitigate CVE-2025-11903

Immediate Actions Required

Restrict network access to ChanCMS administrative endpoints, including /cms/article/update, to trusted IP ranges only
Audit ChanCMS user accounts and disable or rotate credentials for any unused low-privilege accounts
Deploy WAF signatures that block SQL injection payloads targeting the cid parameter until a vendor patch is available

Patch Information

No vendor patch is referenced in the available advisory data. The vendor was contacted prior to disclosure but did not respond. Consult the VulDB entry #328913 for updates on remediation status.

Workarounds

Remove or firewall the /cms/article/update route at the reverse proxy layer if article updates are not required in production
Implement input validation at the reverse proxy or WAF to reject cid values that are not strictly numeric
Apply least-privilege database permissions so the ChanCMS database user cannot modify schema or read unrelated tables

bash

# Example nginx rule to enforce numeric cid values on the article update endpoint
location /cms/article/update {
    if ($arg_cid !~ "^[0-9]+$") {
        return 403;
    }
    proxy_pass http://chancms_backend;
}