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

The Hacker News
Actively Exploited
VulnerabilityCritical

Overview

Hackers have exploited a vulnerability in the Collabora Online - Built-in CODE Server, an optional app for Nextcloud, to gain unauthorized access to Nextcloud servers. The first reported attack occurred on September 10, when three server administrators raised concerns on GitHub. The attackers were able to plant web shells, which are files that allow them to execute commands on the server as if they were the server itself. This type of breach poses a significant risk because it could lead to further exploitation of the server and compromise sensitive data. Users of Nextcloud should take immediate action to secure their servers and apply any available patches to mitigate this vulnerability.

Key Takeaways

  • Active Exploitation: This vulnerability is being actively exploited by attackers. Immediate action is recommended.
  • Affected Systems: Nextcloud servers using the Collabora Online - Built-in CODE Server app
  • Action Required: Users should update to the latest version of the Collabora Online - Built-in CODE Server app and follow security best practices to secure their servers.
  • Timeline: Disclosed on September 10, 2023

Original Article Summary

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 attacker sends via a web request, with the rights of the web server account. The flaw

Impact

Nextcloud servers using the Collabora Online - Built-in CODE Server app

Exploitation Status

This vulnerability is confirmed to be actively exploited by attackers in real-world attacks. Organizations should prioritize patching or implementing workarounds immediately.

Timeline

Disclosed on September 10, 2023

Remediation

Users should update to the latest version of the Collabora Online - Built-in CODE Server app and follow security best practices to secure their servers.

Additional Information

This threat intelligence is aggregated from trusted cybersecurity sources. For the most up-to-date information, technical details, and official vendor guidance, please refer to the original article linked below.

Related Topics: This incident relates to Vulnerability, Critical.

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