CVE-2026-26225 is a local privilege escalation vulnerability found in Intego Personal Backup, a macOS backup utility that enables scheduled backups and creation of bootable system clones. The core issue stems from the way backup task definitions are handled: these task files are stored in locations writable by non-privileged users but are processed with elevated privileges during backup operations. This improper handling allows an attacker with local access to craft a malicious serialized task file that exploits improper link resolution (CWE-59), enabling arbitrary file writes to sensitive system locations such as system binaries or configuration files. By overwriting or injecting malicious content into these critical files, the attacker can escalate their privileges to root, gaining full control over the system. The vulnerability does not require user interaction and can be exploited with low complexity since the attacker only needs local write access to the task definition files. The CVSS 4.0 vector (AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N) reflects a high-severity flaw with significant impact on confidentiality, integrity, and availability. No patches or exploits are currently publicly available, but the vulnerability poses a serious risk to macOS systems running vulnerable versions of Intego Personal Backup.

The impact of CVE-2026-26225 is substantial for organizations using Intego Personal Backup on macOS. Successful exploitation results in local privilege escalation to root, which can compromise the entire system. Attackers gaining root access can bypass all security controls, access sensitive data, install persistent malware, or disrupt backup and recovery processes. This undermines the integrity and availability of critical system backups and may lead to complete system compromise. Since backup utilities are trusted components, exploitation could also facilitate further lateral movement or persistence within an environment. Organizations relying on Intego Personal Backup for disaster recovery or system cloning face increased risk of data loss, unauthorized access, and operational disruption. The vulnerability requires local access but no user interaction, making insider threats or compromised endpoints particularly dangerous vectors.

To mitigate CVE-2026-26225, organizations should immediately restrict write permissions on the directories and files where backup task definitions are stored, ensuring only trusted, privileged users can modify them. Implement file integrity monitoring on these task definition files to detect unauthorized changes. If possible, isolate backup operations to run under least privilege contexts or sandbox the backup process to limit the impact of potential exploits. Monitor system logs for unusual file write activities related to backup tasks. Since no official patches are currently available, consider disabling or limiting the use of Intego Personal Backup until a vendor fix is released. Engage with Intego support for updates and apply patches promptly once available. Additionally, enforce strict local access controls and audit local user activities to reduce the risk of malicious insiders exploiting this vulnerability.