CVE-2026-121501 in CloudClassroom-PHP-Project
Summary
by MITRE • 11/03/2026
A vulnerability was determined in mathurvishal CloudClassroom-PHP-Project. The affected element is the function session_regenerate_id of the file loginlinkadmin.php. Executing a manipulation of the argument PHPSESSID can lead to session fixiation. The attack can be launched remotely. The exploit has been publicly disclosed and may be utilized. This product does not use versioning. This is why information about affected and unaffected releases are unavailable. The vendor was contacted early about this disclosure but did not respond in any way.
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Analysis
by VulDB Data Team • 11/03/2026
The vulnerability identified within the mathurvishal CloudClassroom-PHP-Project represents a critical security flaw rooted in improper session management practices, specifically concerning the implementation of the PHP function session_regenerate_id within the loginlinkadmin.php file. This component is central to maintaining user state during administrative interactions with the cloud-based classroom platform. The core technical deficiency lies in how the application handles the regeneration of session identifiers upon authentication or privilege escalation events. Instead of generating a new, cryptographically secure random identifier and discarding the old one securely, the system allows for manipulation of the PHPSESSID argument. This failure to enforce strict control over session identifier generation creates an opening for attackers to inject their own predetermined session tokens into the application context.
This specific flaw is classified under CWE-384, which denotes Session Fixation. In a typical secure implementation, when a user logs in or gains elevated privileges, the server should invalidate any existing session associated with that user and issue a completely new session ID to prevent an attacker from reusing a previously captured identifier. However, because this product fails to properly regenerate the session ID after authentication events, it remains vulnerable to pre-authentication fixation attacks. An adversary can trick a victim administrator into accessing a malicious link or page where the attacker controls the PHPSESSID value sent in subsequent requests. When the administrator subsequently authenticates through loginlinkadmin.php using their credentials while this manipulated cookie is present, the server binds the administrative session to the attacker-controlled identifier rather than generating a fresh one.
The operational impact of this vulnerability is severe due to its remote exploitability and the high privilege level associated with admin accounts in educational cloud platforms. Since the attack can be launched remotely without requiring physical access or local system privileges, it significantly lowers the barrier for entry for malicious actors. The fact that an exploit has been publicly disclosed further exacerbates the risk landscape, as automated scanning tools and less sophisticated attackers can now easily target instances of this software. Successful exploitation allows an attacker to hijack active administrative sessions, effectively impersonating legitimate administrators. This could lead to unauthorized access to sensitive student data, modification of course materials, deletion of educational resources, or complete compromise of the underlying infrastructure if admin privileges extend beyond the web application layer.
The absence of versioning information in this product complicates remediation efforts for users and security researchers alike. Without clear indicators of which releases are affected versus unaffected, organizations must assume that all deployed instances may be vulnerable unless proven otherwise through direct testing or vendor confirmation. The lack of response from the vendor since early contact suggests a potential gap in their vulnerability management lifecycle, leaving customers without official patches or guidance on mitigation strategies. This silence forces administrators to rely on community-driven insights and defensive coding practices rather than relying on updated software binaries provided by the original developer.
To mitigate this risk, immediate action is required at both the application code level and through compensating controls if patching is not immediately feasible. Developers must ensure that session_regenerate_id is called with the delete_old_session parameter set to true after every successful authentication event or privilege change. This ensures that any previously existing session associated with a user ID is invalidated, preventing reuse of old tokens. Additionally, implementing secure cookie attributes such as HttpOnly and Secure flags can help reduce the risk of client-side script access to session IDs and ensure transmission only over encrypted channels. From an infrastructure perspective, deploying Web Application Firewalls (WAF) with rulesets designed to detect anomalous session ID patterns or fixation attempts can provide a layer of defense in depth.
From a threat intelligence perspective, this vulnerability aligns with MITRE ATT&CK technique T1078, specifically Valid Accounts, as it facilitates unauthorized access by hijacking legitimate credentials and sessions. It also relates to T1528, Steal Application Access Token, since the session ID acts as an application-level token of authentication. Security teams should monitor for unusual login patterns from new IP addresses or devices associated with admin accounts, as these may indicate active exploitation attempts leveraging this flaw. Given that the exploit is public and the vendor has been unresponsive, organizations running this software are advised to treat it as compromised until a verified patch is available or alternative secure solutions are implemented. Regular audits of session management logic across all PHP applications within the environment are recommended to identify similar weaknesses in other components beyond just loginlinkadmin.php.