CVE-2025-5512: Shiyi-blog Auth Bypass Vulnerability

CVE-2025-5512 Overview

CVE-2025-5512 is an authentication bypass vulnerability discovered in quequnlong shiyi-blog, a blog platform application. The vulnerability affects the Administrator Backend component, specifically the /api/sys/user/verifyPassword/ endpoint. Due to improper authentication implementation, remote attackers can bypass security controls and gain unauthorized access to the administrative backend without providing valid credentials.

Critical Impact

Remote attackers can bypass authentication mechanisms to access the administrator backend, potentially leading to complete compromise of the blog platform, data manipulation, and unauthorized administrative actions.

Affected Products

• quequnlong shiyi-blog up to version 1.2.1

Discovery Timeline

• 2025-06-03 - CVE-2025-5512 published to NVD
• 2025-10-03 - Last updated in NVD database

Technical Details for CVE-2025-5512

Vulnerability Analysis

This vulnerability stems from improper authentication handling within the shiyi-blog Administrator Backend. The affected endpoint /api/sys/user/verifyPassword/ fails to properly validate user credentials before granting access to protected administrative functions. This classification falls under CWE-287 (Improper Authentication), which describes scenarios where software does not perform or incorrectly performs authentication of users, entities, or processes.

The vulnerability is remotely exploitable over the network without requiring any authentication or user interaction, making it accessible to any attacker who can reach the vulnerable endpoint. Successful exploitation allows attackers to bypass the screen lock mechanism and gain direct access to the administrative backend interface.

Root Cause

The root cause of this vulnerability is improper authentication implementation in the password verification API endpoint. The /api/sys/user/verifyPassword/ function does not adequately verify user identity before processing requests, allowing attackers to bypass authentication controls entirely. This represents a fundamental flaw in the application's security architecture where authentication checks are either missing, improperly implemented, or can be circumvented through manipulation of request parameters.

Attack Vector

The attack can be launched remotely over the network against the vulnerable API endpoint. An attacker targets the /api/sys/user/verifyPassword/ endpoint in the Administrator Backend component. By manipulating requests to this endpoint, the attacker can bypass the normal authentication flow and gain unauthorized access to administrative functions.

The exploit has been publicly disclosed, increasing the risk of widespread exploitation. The vendor (quequnlong) was contacted about this vulnerability but did not respond, leaving affected installations without an official patch.

For detailed technical analysis of the attack methodology, refer to the GitHub Security Analysis documentation.

Detection Methods for CVE-2025-5512

Indicators of Compromise

• Unusual or unauthorized access attempts to /api/sys/user/verifyPassword/ endpoint
• Administrative backend access from unexpected IP addresses or geographic locations
• Anomalous authentication patterns showing successful backend access without proper credential validation
• Unauthorized modifications to blog content, user accounts, or system configurations

Detection Strategies

• Monitor web server access logs for requests targeting the /api/sys/user/verifyPassword/ endpoint
• Implement Web Application Firewall (WAF) rules to detect and block suspicious authentication bypass attempts
• Deploy behavioral analysis to identify access patterns indicative of authentication bypass exploitation
• Configure alerts for administrative actions performed without corresponding successful authentication events

Monitoring Recommendations

• Enable verbose logging for all authentication-related API endpoints
• Implement real-time alerting for failed and anomalous authentication attempts
• Monitor for unauthorized changes to administrative user accounts or privileges
• Regularly audit access logs for the Administrator Backend component

How to Mitigate CVE-2025-5512

Immediate Actions Required

• Restrict network access to the shiyi-blog administrative backend to trusted IP addresses only
• Implement additional authentication layers (such as VPN or IP whitelisting) before the administrative interface
• Consider temporarily disabling the vulnerable /api/sys/user/verifyPassword/ endpoint if not critical to operations
• Monitor systems for signs of compromise or unauthorized access

Patch Information

No official patch is currently available from the vendor. The vendor (quequnlong) was contacted about this disclosure but did not respond. Users should implement compensating controls and consider migrating to alternative blog platforms with active security maintenance. Monitor the VulDB entry and vendor resources for any future patch releases.

Workarounds

• Deploy a reverse proxy or WAF to filter and block unauthorized access to the administrative API endpoints
• Implement IP-based access control lists to limit administrative backend access to known administrator networks
• Add network-level authentication (such as VPN) as a prerequisite for accessing the administrative interface
• Consider isolating the shiyi-blog application in a restricted network segment with enhanced monitoring

Organizations should implement these compensating controls immediately and evaluate the risk of continued use of this application given the lack of vendor response. For additional technical details, see the GitHub Blog Post documenting this vulnerability.