CVE-2026-46499 · Severity: medium · CVSS 4.3 · Published 2026-10-30
Collabora Online is a web-based office suite that allows multiple users to collaborate on documents. A read-only viewer can send crafted messages to modify documents in real time, misleading other viewers or allowing unauthorized changes that an editor might save without noticing. While changes are lost when the session ends unless an editor saves them, this represents a breach of access controls that could lead to document tampering within active sessions.</brief>
<parameter name="technical_details">Several UNO command and dialog operation code paths in Collabora Online fail to enforce the read-only state flag when the LibreOfficeKit engine processes document operations. A low-privileged read-only user can send crafted WebSocket messages to execute document-mutating operations despite the server-side access control intended to block them. Changes persist only in the live kit process and are discarded on session end unless an authorized editor saves them.
No. Junglewise Threat Intelligence has no report of CVE-2026-46499 being exploited in the wild.
How severe is CVE-2026-46499?
Medium severity, with a CVSS score of 4.3, published 30 October 2026.
Which products and versions are affected?
Collabora Online before 24.04.18 and 25.04.11.
Is there a fix for CVE-2026-46499?
Yes: fixed in 24.04.18, 25.04.11. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-46499 attacked?
It is attacked over the network.
Am I affected by CVE-2026-46499?
Check whether you run Collabora Online at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.