CVE-2026-48750 Incus has an arbitrary file write on host via `exec-output` symlink in crafted image

Description

Incus is a system container and virtual machine manager. Prior to version 7.2.0, the `record-output` parameter of the `/instances/$name/exec` endpoint stores the output of the command in the `exec-output` directory of the instance. If `exec-output` is a symlink, file named `exec_UUID.stdout` and `exec_UUID.stderr` can be written to an arbitrary location where the `.stdout` file will contain arbitrary content. This behavior can be abused for arbitrary command execution. Version 7.2.0 contains a patch.

Exploitable remotely over the network, with an ordinary account and without any user action; an attacker can seriously compromise confidentiality, integrity or availability.

Attack vector

Network

Attack complexity

Low

Privileges required

Low

Interaction

None

Scope

Changed

Confidentiality

High

Integrity

High

Availability

High

Affected products and versions