SECURELYN

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 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.

Scores

9.2
CVSS 9.2 out of 10, critical severity.
1.2%
EPSS 1.2% chance of exploitation in the next 30 days.

The facts

Published
14 October 2026
Last changed
16 October 2026
NVD status
Deferred
Severity
Critical, CVSS 9.2 out of 10 (version 4.0)
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R…
Weakness
Known exploited
Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
EPSS
1.2% chance of exploitation activity in the next 30 days (percentile 68).

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References