CVE-2026-104805 Mitel CVE debrief

Who should care

Defenders and security teams responsible for backup and restoration processes, Linux system administrators, and vulnerability management teams should assess exposure and prioritize remediation.

Why it matters

CVE-2026-104805 is a high-severity vulnerability in an unspecified product's backup restoration functionality. Attackers with access to the backup repository can potentially achieve arbitrary code execution and compromise the underlying virtual machine. Defenders should prioritize verifying backup repository access controls, validating restoration mechanisms, and monitoring for suspicious file extraction activity.

• Potential arbitrary code execution with root privileges
• Compromise of underlying virtual machine
• Unauthorized access to backup repository
• Verification of backup restoration mechanisms and file extraction processes

Technical summary

The backup restoration functionality in an unspecified product fails to properly validate file paths, types, integrity, and authenticity, allowing attackers with repository access to potentially achieve arbitrary code execution. This flaw exists within the backup restoration mechanism, which does not perform file-signature verification before extracting the archive. As a result, a specially crafted backup can contain attacker-controlled files, potentially leading to compromise of the underlying virtual machine if extracted in sensitive locations.

Defensive priority

Defenders should prioritize verifying backup repository access controls, validating restoration mechanisms, and monitoring for suspicious file extraction activity.

Recommended defensive actions

• Verify backup repository access controls and authentication mechanisms
• Validate backup restoration mechanisms and file extraction processes
• Monitor for suspicious file extraction activity and potential code execution
• Implement file signature verification for restored archives
• Enforce backup passwords and access controls

Evidence notes

The CVE record and NVD entry provide details on the vulnerability, but specific affected versions and remediation steps are not provided. The vulnerability exists within the backup restoration mechanism, which fails to properly validate paths, file types, integrity, and authenticity of files contained within a restored TGZ archive. An attacker with access to the backup SFTP or other configured repository can provide a malicious TGZ archive that, when restored by the system, may place arbitrary files on the underlying Linux system. The

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.