CVE-2024-7926: Zzcms Path Traversal Vulnerability

CVE-2024-7926 Overview

CVE-2024-7926 is a path traversal vulnerability in ZZCMS 2023, a Chinese open-source content management system used to build corporate and B2B websites. The flaw resides in the /admin/about_edit.php?action=modify endpoint, where the skin parameter is processed without proper sanitization. Attackers can manipulate this parameter to traverse directories and access files outside the intended scope. The issue has been classified under [CWE-22] (Improper Limitation of a Pathname to a Restricted Directory). Public disclosure of the exploit technique increases the risk of opportunistic attacks against exposed ZZCMS instances.

Critical Impact
Remote attackers can exploit the skin parameter to read or manipulate files outside the intended directory, exposing application configuration and sensitive content on affected ZZCMS 2023 deployments.

Affected Products

ZZCMS 2023
/admin/about_edit.php administrative component
Deployments using the vulnerable skin parameter handler

Discovery Timeline

2024-08-19 - CVE-2024-7926 published to NVD
2024-09-04 - Last updated in NVD database

Technical Details for CVE-2024-7926

Vulnerability Analysis

The vulnerability exists in the administrative file /admin/about_edit.php when invoked with the action=modify query parameter. The skin argument supplied by the requester is passed into file-handling logic without normalization or allow-list validation. As a result, traversal sequences such as ../ allow the application to resolve paths outside the intended skin directory.

Because the affected endpoint is reachable over the network and requires no user interaction, an attacker who can reach the admin interface can issue crafted HTTP requests directly. The exploit technique has been disclosed publicly through VulDB #275112 and a write-up published on Gitee CVE Article: Directory Traversal.

Root Cause

The root cause is improper input validation on the skin parameter. ZZCMS concatenates the user-supplied value into a filesystem path without filtering directory traversal sequences or restricting the resolved path to an expected base directory. This pattern matches the [CWE-22] weakness class.

Attack Vector

An attacker sends a crafted HTTP request to /admin/about_edit.php?action=modify with a malicious value in the skin parameter containing relative path operators. The application interprets the value as a filesystem path, enabling access to resources outside the application's skin directory. No authentication bypass is described in the advisory, but the network-reachable nature of the endpoint makes mass scanning straightforward.

No verified proof-of-concept code is provided in this advisory. Refer to the linked VulDB submission for additional technical context.

Detection Methods for CVE-2024-7926

Indicators of Compromise

HTTP requests to /admin/about_edit.php containing action=modify together with ../ or URL-encoded equivalents (%2e%2e%2f) in the skin parameter.
Web server access logs showing repeated 200 responses to traversal-style skin values from a single source.
Application errors or file-not-found entries referencing paths outside the ZZCMS skin directory.

Detection Strategies

Inspect web server and WAF logs for traversal patterns in query strings targeting ZZCMS administrative endpoints.
Alert on HTTP requests where the skin parameter contains path separators, encoded traversal sequences, or absolute paths.
Correlate administrative endpoint access with unexpected source IPs or anomalous user agents.

Monitoring Recommendations

Enable verbose logging on /admin/* routes and forward logs to a centralized analytics platform for retention and search.
Baseline normal skin parameter values and flag deviations using statistical or signature-based detection rules.
Monitor filesystem access by the PHP worker process for reads outside the ZZCMS web root.

How to Mitigate CVE-2024-7926

Immediate Actions Required

Restrict access to the /admin/ directory using IP allow-lists, VPN, or HTTP authentication at the web server layer.
Deploy WAF rules that block path traversal sequences in the skin query parameter on about_edit.php.
Audit web server logs for prior exploitation attempts referencing the vulnerable endpoint.

Patch Information

No official vendor patch is referenced in the NVD entry or associated advisories at the time of publication. Operators should monitor the VulDB advisory and the ZZCMS project for updates. Until a fix is published, treat ZZCMS 2023 administrative endpoints as untrusted and apply compensating controls.

Workarounds

Remove or rename /admin/about_edit.php if the administrative skin-modification feature is not required.
Add server-side filtering at a reverse proxy to reject requests where the skin parameter contains .., /, \, or null bytes.
Run the PHP process under a least-privilege account with filesystem ACLs restricting reads to the ZZCMS application directory.

bash

# Example NGINX rule to block traversal in the skin parameter
location = /admin/about_edit.php {
    if ($arg_skin ~* "(\.\./|\.\.\\|%2e%2e|/|\\)") {
        return 403;
    }
}