CVE-2026-31940 affects Chamilo LMS, a widely used learning management system. This vulnerability allows attackers to exploit session fixation due to user-controlled request parameters being directly used to set the PHP session ID before loading the global bootstrap. The vulnerability is present in versions prior to 1.11.38 and 2.0.0-RC.3, which means systems running these versions are at risk.
The CVSS score for this vulnerability is 7.5, classifying it as high severity. This score indicates significant risk to organizations, especially since successful exploitation could lead to unauthorized access and manipulation of user sessions. Organizations should prioritize patching immediately.
The vulnerability was disclosed on April 10, 2026, and organizations are urged to update to versions 1.11.38 or 2.0.0-RC.3 to mitigate this risk. Affected systems must be monitored closely for any signs of exploitation, as this could lead to severe consequences.
Current exploitation status shows no known exploits or proof-of-concept code available, but this does not diminish the urgency for remediation.
Vulnerability Details
Chamilo LMS versions before 1.11.38 and 2.0.0-RC.3 are vulnerable to session fixation due to improper handling of user-controlled request parameters. The specific file affected is main/lp/aicc_hacp.php. This vulnerability has been assigned CWE-384, indicating the potential for session fixation attacks.
The CVSS vector for this vulnerability is CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H, highlighting a network attack vector with high attack complexity, no privileges required, and the need for user interaction. The impacts are significant, affecting confidentiality, integrity, and availability.
Technical Analysis
The root cause of this vulnerability lies in the handling of user input for setting the PHP session ID without proper validation or sanitation. The attack vector is network-based, requiring users to interact with the system, making it a user-driven attack. The complexity of the attack is rated as high, indicating that while exploitation is possible, it may not be straightforward.
No privileges are required to exploit this vulnerability, but user interaction is necessary, as the attacker must manipulate the session through crafted requests. If successful, attackers could gain access to user sessions, potentially leading to unauthorized actions within the application.
Risk & Impact Analysis
Risk to organizations includes unauthorized access to user sessions, which can lead to data breaches or unauthorized manipulation of sensitive information within the Chamilo LMS. Given the educational context in which Chamilo operates, this risk is amplified as it may involve student information and educational resources.
The potential blast radius for this vulnerability is considerable, affecting all users of the affected versions. The exploitation of this vulnerability could result in significant reputational damage and legal implications for organizations that fail to address it promptly.
Organizations should address this vulnerability in their priority patch cycle, especially given the high CVSS score and the potential impact on sensitive data.
Exploitation Status
Signal | Status |
|---|---|
Known Exploit | No |
Public PoC | No |
Actively Exploited | No |
Ransomware Use | No |
Affected Versions
The vulnerable versions of Chamilo LMS include any version prior to 1.11.38 and 2.0.0-RC.3. This includes various alpha, beta, and release candidate versions leading up to these fixed versions.
Mitigation & Remediation
Organizations should immediately upgrade to Chamilo LMS version 1.11.38 or 2.0.0-RC.3 to mitigate this vulnerability. In cases where an immediate upgrade is not possible, consider implementing configuration hardening measures to restrict access to the application and monitor for unusual activity.
Regular monitoring and security assessments should be conducted to ensure ongoing protection against potential exploitation of this vulnerability. For further assistance, organizations can leverage penetration testing services to evaluate the security posture.
Detection Guidance
Organizations should look for unusual session behavior and monitor logs for unauthorized session ID changes. Additionally, behavioral anomalies such as unexpected user activity should be flagged for review.
AppSecure Threat Intelligence Insight
The long-term significance of CVE-2026-31940 highlights the need for organizations to maintain robust input validation practices to prevent session fixation vulnerabilities. This incident serves as a reminder of the importance of regular updates and security assessments to identify and remediate weaknesses in web applications.
Organizations should consider adopting a proactive security strategy by integrating penetration testing methodology into their development lifecycle to identify vulnerabilities early. By doing so, they can reduce the risk of exploitation and increase their overall security posture.
In addition, employing strategies from our vulnerability management program can help organizations effectively track and address security issues as they arise.
Finally, engaging in continuous security testing through our continuous penetration testing service can help organizations stay ahead of emerging threats and vulnerabilities.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
.webp)