Actively exploited · Published Oct 14, 2026 · Assigned by mitre

CVE-2026-110447

Critical 9.2 Exploited

In plain English

A critical-severity OS command injection in Collabora Online - Built-in CODE Server from Collabora. Attackers are actively exploiting it in the wild (listed by CISA on October 23, 2026). The chance it is exploited in the next 30 days is estimated at 73.3% (higher than 99.5% of all known vulnerabilities). Ready-made attack tooling exists: Nuclei, public proof-of-concept code. 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 each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

Severity (CVSS 4.0)9.2Critical
Exploit odds (30 days)73.3%top 0.5% of all CVEs
Exploited in the wildYesCISA KEV since Oct 23, 2026
Attack tooling2Nuclei, Public PoC

CISA guidance

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 each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

Federal agencies must remediate by Oct 26, 2026.

Official description

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.

Affected products (as reported)

VendorProductVersions
Collabora Collabora Online - Built-in CODE Server 0 – before 26.4.303

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

References