CVE-2026-110447 Collabora Online – Built-in CODE Server OS Command Injection

Exploited in the wild Critical 9.2 Published 14 Oct 2026 Updated 24 Oct 2026

Remote attackers can execute arbitrary OS commands via proxy.php when the CODE server is not running, affecting Nextcloud deployments using this specific built-in server.

Exploited in the wild: Since 23 Oct 2026
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2026-110447?

CVE-2026-110447 is a critical command injection vulnerability in Collabora Online - Built-in CODE Server, published on 14 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

Collabora Online Built-in CODE Server before 26.4.303 (richdocumentscode), a Nextcloud app, allows remote code execution, as exploited in the wild in September and October 2026, a different vulnerability than CVE-2025-66208. This is an OS command injection in proxy.php when the CODE server isn't running (e.g., the product was recently restarted). The vulnerability is not present in standalone Collabora Online servers; only this deployment with CODE Server is affected.

Weakness: CWE-78

Which versions are affected by CVE-2026-110447?

It affects 1 product.

Products include Collabora Online.

How do I fix CVE-2026-110447?

No fix has been published for CVE-2026-110447 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 26 Oct 2026.

Upgrade, and pass arguments to programs as a list instead of through a shell. More about Command injection.

Is CVE-2026-110447 being exploited?

Yes. Attackers have exploited CVE-2026-110447 in the wild since at least 23 Oct 2026.

Public exploit code: 1 Nuclei template and 2 proofs of concept on GitHub.

Sources

Also known as GHSA-f97p-r72q-64h2.