CVE-2025-67298: ClassroomIO Privilege Escalation Flaw

CVE-2025-67298 Overview

CVE-2025-67298 is a privilege escalation vulnerability discovered in ClassroomIO, an open-source Learning Management System (LMS) platform. The vulnerability exists in versions prior to v0.2.6 and allows remote attackers to escalate privileges by exploiting weaknesses in the /api/verify and /rest/v1/profile endpoints. This authentication bypass vulnerability (CWE-290) enables unauthorized users to gain elevated access rights within the application.

Critical Impact

Remote attackers can exploit this vulnerability to bypass authentication mechanisms and escalate privileges, potentially gaining administrative access to the ClassroomIO platform without proper authorization.

Affected Products

• ClassroomIO versions before v0.2.6

Discovery Timeline

• 2026-03-11 - CVE-2025-67298 published to NVD
• 2026-03-12 - Last updated in NVD database

Technical Details for CVE-2025-67298

Vulnerability Analysis

This vulnerability stems from Authentication Bypass by Spoofing (CWE-290) within the ClassroomIO application. The vulnerable endpoints /api/verify and /rest/v1/profile fail to properly validate authentication tokens or user identity claims, allowing attackers to manipulate requests to impersonate other users or escalate their privileges within the system.

The attack can be executed over the network without requiring any user interaction, though exploitation complexity is considered high. Successful exploitation can result in complete compromise of confidentiality, integrity, and availability of the affected system. In a Learning Management System context, this could allow attackers to access sensitive student data, modify course content, manipulate grades, or gain full administrative control over the platform.

Root Cause

The root cause of this vulnerability lies in improper authentication verification within the affected API endpoints. The /api/verify endpoint, designed to validate user authentication status, and the /rest/v1/profile endpoint, used for profile management, do not adequately verify that the requesting user has legitimate authorization to perform the requested operations. This authentication bypass allows attackers to forge or manipulate authentication parameters to assume the identity of other users, including administrators.

Attack Vector

The attack is network-based and can be executed remotely against any ClassroomIO deployment running a vulnerable version. An attacker would craft malicious requests to the /api/verify or /rest/v1/profile endpoints, manipulating authentication parameters to bypass identity verification checks. Once successful, the attacker can escalate from an unprivileged or unauthenticated state to a higher privilege level.

The vulnerability mechanism involves sending specially crafted HTTP requests to the vulnerable endpoints that exploit weaknesses in the authentication verification logic. For detailed technical analysis, refer to the security researcher's gist.

Detection Methods for CVE-2025-67298

Indicators of Compromise

• Unusual authentication patterns or repeated requests to /api/verify with varying authentication parameters
• Unexpected profile access or modifications via /rest/v1/profile from unknown IP addresses
• User accounts showing activity from multiple geographic locations simultaneously
• Administrative actions performed by non-administrative accounts

Detection Strategies

• Implement logging and monitoring for all requests to /api/verify and /rest/v1/profile endpoints
• Deploy Web Application Firewall (WAF) rules to detect and block anomalous authentication request patterns
• Monitor for privilege escalation attempts by tracking user permission changes
• Correlate authentication events with profile modification activities

Monitoring Recommendations

• Enable verbose logging on ClassroomIO API endpoints to capture request details
• Set up alerting for failed authentication attempts followed by successful profile access
• Monitor for unusual administrative actions from recently created or previously inactive accounts
• Review access logs regularly for patterns indicative of authentication bypass attempts

How to Mitigate CVE-2025-67298

Immediate Actions Required

• Upgrade ClassroomIO to version v0.2.6 or later immediately
• Review user account permissions and audit recent administrative changes for signs of unauthorized access
• Implement network-level restrictions to limit access to the ClassroomIO administrative interface
• Monitor logs for any indicators of prior exploitation

Patch Information

The ClassroomIO development team has released version v0.2.6 which addresses this privilege escalation vulnerability. Administrators should upgrade to this version or later to remediate the vulnerability. The patch is available through the official ClassroomIO GitHub releases page.

Workarounds

• Restrict access to /api/verify and /rest/v1/profile endpoints through reverse proxy or firewall rules until patching is complete
• Implement additional authentication layers such as multi-factor authentication (MFA) for all user accounts
• Deploy a Web Application Firewall (WAF) with custom rules to inspect and validate requests to vulnerable endpoints
• Consider temporarily disabling public registration if the platform is exposed to the internet

# Example: Nginx configuration to restrict access to vulnerable endpoints
location ~ ^/(api/verify|rest/v1/profile) {
    # Allow only from trusted internal networks until patch is applied
    allow 10.0.0.0/8;
    allow 192.168.0.0/16;
    deny all;
    
    proxy_pass http://classroomio_backend;
}