CVE-2023-41266 is a path traversal vulnerability identified in Qlik Sense Enterprise for Windows across several patch versions released before August 2023. The vulnerability stems from improper validation of file path inputs, classified under CWE-22, allowing an unauthenticated remote attacker to generate an anonymous session. This session creation bypasses normal authentication mechanisms, enabling the attacker to send crafted HTTP requests to unauthorized internal endpoints within the Qlik Sense environment. Such unauthorized access can lead to exposure of sensitive information, compromising confidentiality. The vulnerability has a CVSS 3.1 base score of 8.2, reflecting its high severity due to network attack vector, no required privileges or user interaction, and significant confidentiality impact with limited integrity impact. The flaw affects multiple patch levels, including May 2023 Patch 3 and earlier, February 2023 Patch 7 and earlier, November 2022 Patch 10 and earlier, and August 2022 Patch 12 and earlier. The vendor addressed the issue in the August 2023 Interim Release and subsequent patches. Although no active exploitation has been reported, the vulnerability's characteristics make it a critical risk for organizations running vulnerable Qlik Sense versions, as attackers can remotely exploit it without authentication or user interaction. This can lead to unauthorized data access and potential lateral movement within enterprise environments.

For European organizations, the vulnerability poses a significant risk to confidentiality of sensitive business intelligence data managed via Qlik Sense Enterprise. Attackers exploiting this flaw can bypass authentication controls and access unauthorized endpoints, potentially extracting or manipulating sensitive reports and datasets. This is particularly concerning for sectors such as finance, healthcare, manufacturing, and government agencies that rely heavily on Qlik Sense for data analytics and decision-making. The integrity impact is limited but still present due to possible unauthorized requests. Availability is not directly affected. Exploitation ease and lack of required privileges increase the threat level. Data breaches resulting from this vulnerability could lead to regulatory penalties under GDPR, reputational damage, and operational disruptions. Organizations with exposed Qlik Sense management interfaces or insufficient network segmentation are at higher risk. The absence of known exploits in the wild provides a window for proactive mitigation but should not reduce urgency.

1. Immediately apply the vendor-released patches: August 2023 Interim Release, May 2023 Patch 4, February 2023 Patch 8, November 2022 Patch 11, or August 2022 Patch 13, depending on your installed version. 2. Restrict network access to Qlik Sense management and API endpoints using firewalls or network segmentation to limit exposure to trusted internal networks only. 3. Implement strict access controls and monitor logs for anomalous anonymous session creation or unusual HTTP requests targeting internal endpoints. 4. Conduct a thorough audit of Qlik Sense configurations to ensure no unnecessary services or endpoints are exposed externally. 5. Educate security teams about this vulnerability to enable rapid detection and response to potential exploitation attempts. 6. Consider deploying Web Application Firewalls (WAF) with custom rules to detect and block path traversal attempts targeting Qlik Sense. 7. Regularly review and update incident response plans to include scenarios involving unauthorized access through Qlik Sense vulnerabilities.