CVE-2026-12080 Qemu-kvm: qemu-guest-agent: local privilege escalation via symlink attack in guest-ssh-add-authorized-keys

Description

A flaw was found in the QEMU Guest Agent (qga). A local unprivileged user can exploit a vulnerability in the guest-ssh-add-authorized-keys command handler by manipulating symbolic links. This can occur either through a deterministic directory-symlink bypass or a Time-of-Check to Time-of-Use (TOCTOU) file-symlink race. Successful exploitation allows the attacker to gain ownership of arbitrary root-owned files or directories, leading to root access. This vulnerability requires an external management layer (e.g., libvirt) to trigger the affected code path.

Exploitable with local access to the machine, with an ordinary account and if a user takes an action; an attacker can seriously compromise confidentiality, integrity or availability.

Attack vector

Local

Attack complexity

Low

Privileges required

Low

Interaction

Required

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Affected products and versions