CVE-2026-20960 is an improper authorization vulnerability (CWE-285) identified in Microsoft Power Apps Desktop Client version 1.0.0. This flaw allows an attacker who is already authorized with limited privileges to execute arbitrary code remotely over a network. The vulnerability arises because the application fails to properly enforce authorization checks before allowing certain actions, enabling privilege escalation and remote code execution (RCE). The CVSS v3.1 score of 8.0 reflects a high-severity issue, with an attack vector over the network (AV:N), low attack complexity (AC:L), requiring privileges (PR:L), and user interaction (UI:R). The scope is unchanged (S:U), but the impact on confidentiality, integrity, and availability is high (C:H/I:H/A:H). Although no exploits are currently known in the wild, the vulnerability poses a significant risk due to the potential for attackers to gain full control over affected systems. The lack of available patches at the time of publication necessitates immediate mitigation efforts. Power Apps Desktop Client is widely used for building and running custom business applications, making this vulnerability particularly concerning for organizations relying on these applications for critical operations.

For European organizations, this vulnerability could lead to severe consequences including unauthorized access to sensitive data, disruption of business-critical applications, and potential lateral movement within corporate networks. Given Power Apps' integration with various enterprise systems, exploitation could compromise multiple layers of an organization's IT infrastructure. Confidentiality breaches could expose personal data protected under GDPR, leading to regulatory penalties and reputational damage. Integrity and availability impacts might disrupt operational workflows, causing financial losses and service outages. The requirement for user interaction and existing privileges somewhat limits the attack surface, but insider threats or phishing campaigns could facilitate exploitation. Organizations in sectors such as finance, healthcare, and government, which heavily utilize Microsoft Power Apps for custom solutions, are particularly vulnerable to operational and compliance risks stemming from this flaw.

Until official patches are released, organizations should implement strict access controls to limit user privileges on systems running Power Apps Desktop Client. Employ application whitelisting to prevent unauthorized code execution and monitor network traffic for unusual activity related to Power Apps processes. Conduct user awareness training to reduce the risk of social engineering attacks that could trigger exploitation. Review and harden authorization policies within Power Apps environments to ensure least privilege principles are enforced. Utilize endpoint detection and response (EDR) tools to detect anomalous behavior indicative of exploitation attempts. Coordinate with Microsoft for timely patch deployment once available and test updates in controlled environments before widespread rollout. Additionally, consider isolating Power Apps Desktop Client usage to segmented network zones to minimize potential lateral movement.