Collabora Online – Built-in CODE Server OS Command Injection Vulnerability. Actively exploited: CISA added this vulnerability to its Known Exploited Vulnerabilities catalog on 23/10/2026. Patch affected systems as an emergency.
| Package | Affected versions | Patched versions |
|---|---|---|
| collabora online - built-in code server | < 26.4.303 | 26.4.303 |
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.
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