CVE-2022-39238 is a medium-severity vulnerability affecting the open source biomedical big data platform Arvados, specifically versions prior to 2.4.3. The vulnerability arises from improper authentication handling when using Portable Authentication Modules (PAM) as the user authentication method. In affected versions, if a user presents valid credentials but their account is disabled or otherwise restricted from accessing the host system—such as due to an expired password—the system erroneously grants access to Arvados. This flaw violates proper authentication principles by failing to enforce account status checks beyond credential validity. It is important to note that this issue is isolated to PAM authentication; other supported authentication methods like LDAP and OpenID Connect are not impacted. The vulnerability is classified under CWE-287 (Improper Authentication), indicating a failure to correctly verify user identity and authorization. The issue was publicly disclosed on September 23, 2022, and patched in Arvados version 2.4.3. No known exploits have been reported in the wild. A practical workaround prior to patching is to migrate from PAM to alternative authentication methods such as LDAP, which do not exhibit this flaw. This vulnerability could allow unauthorized access to sensitive biomedical data and computational resources managed by Arvados, potentially leading to data confidentiality breaches and unauthorized data manipulation or disruption of services.

For European organizations, particularly those involved in biomedical research, healthcare data analysis, and life sciences, this vulnerability poses a significant risk. Arvados is used to manage and analyze large-scale biomedical datasets, which often include sensitive patient information and proprietary research data. Unauthorized access due to improper authentication could lead to exposure of confidential health data, violating GDPR and other data protection regulations, resulting in legal and financial repercussions. Additionally, attackers gaining access might manipulate or corrupt critical biomedical data, undermining research integrity and operational continuity. The impact extends to availability if attackers disrupt processing pipelines or computational workflows. Given the specialized nature of Arvados, organizations relying on PAM authentication are at higher risk until patched or migrated. The absence of known exploits suggests limited active targeting so far, but the potential for insider threats or opportunistic attackers exploiting weak authentication remains. The medium severity reflects a balance between the ease of exploitation (valid credentials required) and the serious consequences of unauthorized access to sensitive biomedical environments.

To mitigate this vulnerability, European organizations using Arvados with PAM authentication should prioritize upgrading to version 2.4.3 or later where the issue is patched. If immediate patching is not feasible, migrating authentication away from PAM to supported methods such as LDAP or OpenID Connect is strongly recommended, as these methods are not affected by this flaw. Organizations should audit their current authentication configurations to identify PAM usage and disabled or expired accounts that might be improperly accepted. Implementing strict account lifecycle management and monitoring for anomalous login activity can help detect exploitation attempts. Additionally, integrating multi-factor authentication (MFA) with supported authentication methods can further reduce risk. Network segmentation and access controls limiting Arvados access to trusted users and systems will reduce exposure. Regularly reviewing and updating authentication policies and ensuring compliance with GDPR and other relevant regulations is critical. Finally, organizations should maintain up-to-date backups of biomedical data and workflows to recover from potential data integrity attacks.