Hackers exploit Collabora RCE flaw to backdoor Nextcloud servers
Threat actors are exploiting a critical command execution flaw, now tracked as CVE-2026-110447, in the Collabora Online - Built-in CODE Server app (richdocumentscode) for Nextcloud. Multiple administrator reports indicate that attacks began in mid-September, roughly a month before the formal security bulletin, the GitHub advisory, and CVE publication. CVE-2026-110447 impacts richdocumentscode versions before 26.4.303 and resides in the Nextcloud app’s mechanism for starting the bundled Collabora server. The flaw affects only the optional built-in CODE server app. Standalone Collabora Online










