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) release 23.5.403. Users are advised to upgrade. There are no known workarounds for this vulnerability.
Severity
CVSS 3.1
6.1 medium
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
EPSS
0.4% chance of exploitation in the next 30 days; higher than 34% of CVEs (scores of 2026-10-31)