Hackers Backdoor Nextcloud Servers Through Critical Flaw in Collabora’s Built-in CODE App

Attackers exploited a flaw in an optional Nextcloud app, Collabora Online - Built-in CODE Server, to plant web shells on Nextcloud servers. Three administrators reported the issue on GitHub, with the first logged attack on September 10. A web shell is a small file that executes any command an...

CVE-2026-110447

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...

CVE-2026-110447

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...

CVE-2026-110447

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...

CVE-2026-110447

The Collabora Online Built-in CODE Server (Nextcloud app richdocumentscode ) is vulnerable to remote code execution (RCE) via an OS command injection in the proxy.php script. The flaw occurs specifically when the CODE server is not running, such as immediately after a restart, crash, or upgrade. ...

EUVD-2026-100780

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...

CVE-2026-110447: Improper Neutralization of Special Elements used in an OS Command

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...

VulnCheck KEV: CVE-2026-110447

Collabora Collabora Online – Built-in CODE Server when used within the NextCloud platform contains an OS command injection vulnerability that allows for remote code execution when the CODE server isn't running...

PT-2026-113607

Name of the Vulnerable Software and Affected Versions Collabora Online Built-in CODE Server richdocumentscode versions prior to 26.4.303 Description An OS command injection issue exists in the proxy.php endpoint of the richdocumentscode app. The flaw occurs when the built-in CODE server is not...

CVE-2023-49788

Collabora Online is a collaborative online office suite based on LibreOffice technology. Unlike a standalone dedicated Collabora Online server, the Built-in CODE Server richdocumentscode is run without chroot sandboxing. Vulnerable versions of the richdocumentscode app can be susceptible to attac...

CVE-2025-66208

Collabora Online - Built-in CODE Server richdocumentscode provides a built-in server with all of the document editing features of Collabora Online. In versions prior to 25.04.702, Collabora Online has a Configuration-Dependent RCE OS Command Injection in richdocumentscode proxy. Users of Nextclou...

CVE-2025-66208 Configuration-Dependent RCE (OS Command Injection) in richdocumentscode proxy

Collabora Online - Built-in CODE Server richdocumentscode provides a built-in server with all of the document editing features of Collabora Online. In versions prior to 25.04.702, Collabora Online has a Configuration-Dependent RCE OS Command Injection in richdocumentscode proxy. Users of Nextclou...

EUVD-2023-52370

Malicious code in bioql PyPI...

CVE-2023-49782

Collabora Online is a collaborative online office suite based on LibreOffice technology. Users of Nextcloud with "Collabora Online - Built-in CODE Server" app can be vulnerable to attack via proxy.php. The bug was fixed in Collabora Online - Built-in CODE Server richdocumentscode release 23.5.601...

CVE-2023-49788 Improper handling of browser-side provided input in richdocuments path handling

Collabora Online is a collaborative online office suite based on LibreOffice technology. Unlike a standalone dedicated Collabora Online server, the Built-in CODE Server richdocumentscode is run without chroot sandboxing. Vulnerable versions of the richdocumentscode app can be susceptible to attac...

CVE-2023-49782: Improper Neutralization of Input During Web Page Generation

Collabora Online is a collaborative online office suite based on LibreOffice technology. Users of Nextcloud with Collabora Online - Built-in CODE Server app can be vulnerable to attack via proxy.php. The bug was fixed in Collabora Online - Built-in CODE Server richdocumentscode release 23.5.601...

CVE-2023-48314

Collabora Online is a collaborative online office suite based on LibreOffice technology. Users of Nextcloud with Collabora Online Built-in CODE Server app can be vulnerable to attack via proxy.php. This vulnerability has been fixed in Collabora Online - Built-in CODE Server richdocumentscode...

PT-2023-8434 · Collabora +2 · Collabora Online +2

Name of the Vulnerable Software and Affected Versions: Collabora Online - Built-in CODE Server richdocumentscode versions prior to 23.5.403 Description: The issue is related to the proxy.php component of Collabora Online, which is a collaborative online office suite based on LibreOffice technolog...

CVE-2023-48314: Improper Neutralization of Input During Web Page Generation

Collabora Online is a collaborative online office suite based on LibreOffice technology. Users of Nextcloud with Collabora Online Built-in CODE Server app can be vulnerable to attack via proxy.php. This vulnerability has been fixed in Collabora Online - Built-in CODE Server richdocumentscode...