CVE-2022-41918 is a security vulnerability affecting the OpenSearch project, an open source fork of Elasticsearch and Kibana widely used for search and analytics. The vulnerability arises from an incorrect implementation of fine-grained access control mechanisms, specifically related to document-level security, field-level security, and field masking. These controls are intended to restrict user access to sensitive data within indices. However, the vulnerability causes these access control rules to be improperly applied to the indices backing data streams. This misapplication can lead to unauthorized access, allowing users to view or manipulate data they should not have permission to access. The affected versions include all OpenSearch releases prior to 1.3.7 and versions from 2.0.0 up to but not including 2.4.0. The issue was addressed in OpenSearch versions 1.3.7 and 2.4.0. No known workarounds exist, making patching the only effective remediation. Although there are no known exploits in the wild, the vulnerability is classified under CWE-863 (Incorrect Authorization) and CWE-612 (Improper Authorization of Index Containing Sensitive Information), highlighting the risk of unauthorized data exposure due to flawed authorization logic. This vulnerability impacts confidentiality and integrity by potentially exposing sensitive information and allowing unauthorized data manipulation. The vulnerability does not require user interaction but does require an attacker to have some level of access to the OpenSearch environment, which is typically used in enterprise and cloud environments for data indexing and search functionalities.

For European organizations, the impact of CVE-2022-41918 can be significant, especially for those relying on OpenSearch for critical data analytics, logging, and search services. Unauthorized access to sensitive data could lead to breaches of personal data protected under GDPR, resulting in legal and financial penalties. The exposure of confidential business intelligence or operational data could undermine competitive advantage and damage reputation. Additionally, incorrect authorization could allow malicious insiders or compromised accounts to escalate privileges or exfiltrate sensitive information. Given OpenSearch’s use in sectors such as finance, healthcare, telecommunications, and government, the vulnerability could affect the confidentiality and integrity of sensitive datasets, potentially disrupting operations and eroding trust. The absence of workarounds means organizations must prioritize patching to mitigate these risks. The vulnerability could also impact availability indirectly if unauthorized actions lead to data corruption or operational disruptions.

To mitigate CVE-2022-41918, European organizations should: 1) Immediately upgrade OpenSearch installations to version 1.3.7 or 2.4.0 or later, depending on their current version branch. 2) Conduct a thorough audit of access control policies and verify that fine-grained access controls are correctly configured and enforced post-patch. 3) Restrict access to OpenSearch clusters to trusted administrators and enforce strong authentication and authorization mechanisms to limit the attack surface. 4) Monitor OpenSearch logs and access patterns for unusual activity that could indicate exploitation attempts or unauthorized access. 5) Implement network segmentation and firewall rules to isolate OpenSearch clusters from untrusted networks. 6) Review and update incident response plans to include scenarios involving unauthorized data access through search infrastructure. 7) Engage in regular vulnerability scanning and penetration testing focused on authorization controls within OpenSearch environments. These steps go beyond generic advice by emphasizing configuration audits, monitoring, and network-level protections tailored to the nature of this vulnerability.