CVE-2023-49339 is a security vulnerability identified in Ellucian Banner version 9.17, a widely used enterprise resource planning (ERP) system tailored for higher education institutions. The vulnerability is classified as an Insecure Direct Object Reference (IDOR), which occurs when an application exposes a reference to an internal implementation object, such as a file, directory, or database key, without proper access control. Specifically, this vulnerability arises from the /StudentSelfService/ssb/studentCard/retrieveData endpoint, where an attacker can manipulate the 'bannerId' parameter to access data belonging to other users without authorization. The vulnerability does not require user interaction and can be exploited remotely over the network (AV:N), with low attack complexity (AC:L), but requires some level of privileges (PR:L), such as a valid authenticated user. The CVSS v3.1 base score is 6.5, indicating a medium severity level. The impact primarily affects confidentiality (C:H), with no impact on integrity (I:N) or availability (A:N). No known exploits are currently reported in the wild, and no patches or vendor advisories have been linked yet. The vulnerability is associated with CWE-639, which relates to authorization bypass through improper validation of object references. Given the nature of the vulnerability, an attacker with legitimate access could escalate their privileges to view sensitive student information belonging to others, potentially leading to privacy violations and compliance issues.

For European organizations, particularly universities and educational institutions using Ellucian Banner 9.17, this vulnerability poses a significant risk to the confidentiality of student data. Unauthorized access to personal and academic records could lead to breaches of the EU General Data Protection Regulation (GDPR), resulting in legal penalties and reputational damage. The exposure of sensitive student information could also facilitate identity theft, phishing attacks, or social engineering campaigns targeting students and staff. Since the vulnerability requires authenticated access, insider threats or compromised user credentials could be leveraged by attackers to exploit this flaw. The lack of impact on integrity and availability reduces the risk of data manipulation or service disruption, but the confidentiality breach alone is critical in the context of personal data protection laws in Europe. Institutions may face increased scrutiny from data protection authorities and loss of trust from their communities if exploited.

Organizations should implement strict access control checks on the /StudentSelfService/ssb/studentCard/retrieveData endpoint to ensure that users can only access their own records. This includes validating the 'bannerId' parameter against the authenticated user's identity and enforcing server-side authorization checks. Monitoring and logging access to sensitive endpoints should be enhanced to detect anomalous access patterns indicative of exploitation attempts. Since no official patch is currently available, organizations should consider temporary compensating controls such as restricting access to the affected endpoint to trusted networks or roles, applying web application firewalls (WAF) rules to detect and block suspicious parameter tampering, and conducting regular audits of user permissions. Additionally, institutions should enforce strong authentication mechanisms and credential hygiene to reduce the risk of account compromise. Prompt application of vendor patches once released is essential. Finally, raising awareness among IT staff and users about the risks of credential misuse can help mitigate exploitation.