Red Hat QEMU Command guest-ssh-add-authorized-keys toctou

Summaryinfo

A vulnerability classified as very critical has been found in Red Hat QEMU. This vulnerability affects the function guest-ssh-add-authorized-keys of the component Command Handler. The manipulation leads to toctou. This vulnerability is listed as CVE-2026-12080. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability, which was classified as very critical, has been found in Red Hat QEMU (version now known). This issue affects the function guest-ssh-add-authorized-keys of the component Command Handler. The manipulation with an unknown input leads to a toctou vulnerability. Using CWE to declare the problem leads to CWE-367. The product checks the state of a resource before using that resource, but the resource's state can change between the check and the use in a way that invalidates the results of the check. This can cause the product to perform invalid actions when the resource is in an unexpected state. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at access.redhat.com. The identification of this vulnerability is CVE-2026-12080 since 06/12/2026. The exploitation is known to be easy. The attack may be initiated remotely. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $5k-$25k at the moment (estimation calculated on 07/20/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-45941). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• Virtualization Software

Vendor

• Red Hat

Name

• QEMU

License

• open-source

Website

• Vendor: https://www.redhat.com/

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• 🔒

CPE 2.2info

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Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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