CVE-2026-110447: Collabora Online – Built-in CODE Server (Critical, CVSS 9.2)
- CVSS
- 9.2 Critical (v4.0)
- EPSS
- 12.3% chance of exploitation in the next 30 days (higher than 96.1% of CVEs)
- Exploited in the wild
- Yes, on CISA’s KEV list since Oct 23, 2026
- Public exploit
- Yes, reported in 1 GitHub repository
- Weakness
- CWE-78
- Vector
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- Published
- Oct 14, 2026
- CISA fix-by date
- Oct 26, 2026 (for US federal agencies)
What it is
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.
Description from the National Vulnerability Database.
What to do
CISA: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating
Check whether you run Collabora Online – Built-in CODE Server, then apply the vendor’s fix or mitigation from the advisories below. Because this flaw is exploited or has public exploit code, treat it as urgent and check for signs of compromise, not just the patch level.
Advisories and fixes
Sources: NVD, FIRST EPSS, CISA KEV, and public exploit databases (availability only). ThreatRoundup reports whether public exploit code exists but never links to it: fake proof-of-concepts that infect security researchers are common. This page updates automatically.