This vulnerability (CVE-2026-58617) in Microsoft 365 Copilot for iOS is classified as CWE-284 (Improper Access Control). It allows an attacker without privileges to elevate their privileges remotely over a network, potentially gaining unauthorized access to sensitive information or functionality. The CVSS 3.1 vector indicates network attack vector, low attack complexity, no privileges required, user interaction required, unchanged scope, high confidentiality and integrity impact, no availability impact, and an official fix is available. Since Microsoft 365 Copilot for iOS is a cloud service, Microsoft manages the remediation server-side.

Successful exploitation can lead to unauthorized privilege escalation, compromising confidentiality and integrity of data or operations within Microsoft 365 Copilot for iOS. There is no impact on availability. The vulnerability allows attackers to gain higher access rights than intended, potentially exposing sensitive information or enabling unauthorized actions.

An official fix is available from Microsoft. As this is a cloud-hosted service, Microsoft manages the remediation on their servers. Users and administrators should ensure that the service is updated according to Microsoft's guidance. Refer to the Microsoft security update guide at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-58617 for detailed remediation instructions.