CVE-2026-46499
Collabora Online: Read-only session authorization bypass permits live document edits
Collabora Online is a collaborative online office suite based on LibreOffice technology. Prior to 24.04.18 and 25.04.11, several document operations delegated to LibreOfficeKit in the per-document kit process fail to enforce a session's read-only state. A read-only user, such as a viewer-role WOPI user, can send crafted WebSocket messages to execute document-mutating UNO commands and dialog operations despite the read-only interface. The changes can mislead co-viewers within the live session, or an authorized editor sharing the session can unknowingly save the modifications. The read-only attacker cannot save the document directly, and changes are discarded when the kit session ends unless an authorized editor saves them. This issue is fixed in versions 24.04.18 and 25.04.11.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Collabora Online: Read-only session authorization bypass permits live document edits
Collabora Online is a collaborative online office suite based on LibreOffice technology. Prior to 24.04.18 and 25.04.11, several document operations delegated to LibreOfficeKit in the per-document kit process fail to enforce a session's read-only state. A read-only user, such as a viewer-role WOPI user, can send crafted WebSocket messages to execute document-mutating UNO commands and dialog operations despite the read-only interface. The changes can mislead co-viewers within the live session, or an authorized editor sharing the session can unknowingly save the modifications. The read-only attacker cannot save the document directly, and changes are discarded when the kit session ends unless an authorized editor saves them. This issue is fixed in versions 24.04.18 and 25.04.11.
- Record
CVE-2026-46499- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-863
- Updated
- 2026-11-05
EUVDEUVD-2026-114090
Collabora Online is a collaborative online office suite based on LibreOffice technology. Prior to 24.04.18 and 25.04.11, several document operations delegated to LibreOfficeKit in the per-document kit process fail to enforce a session's read-only state. A read-only user, such as a viewer-role WOPI user, can send crafted WebSocket messages to execute document-mutating UNO commands and dialog operations despite the read-only interface. The changes can mislead co-viewers within the live session, or an authorized editor sharing the session can unknowingly save the modifications. The read-only attacker cannot save the document directly, and changes are discarded when the kit session ends unless an authorized editor saves them. This issue is fixed in versions 24.04.18 and 25.04.11.
- Record
EUVD-2026-114090- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N - Updated
- 2026-11-05
NVD
Collabora Online is a collaborative online office suite based on LibreOffice technology. Prior to 24.04.18 and 25.04.11, several document operations delegated to LibreOfficeKit in the per-document kit process fail to enforce a session's read-only state. A read-only user, such as a viewer-role WOPI user, can send crafted WebSocket messages to execute document-mutating UNO commands and dialog operations despite the read-only interface. The changes can mislead co-viewers within the live session, or an authorized editor sharing the session can unknowingly save the modifications. The read-only attacker cannot save the document directly, and changes are discarded when the kit session ends unless an authorized editor saves them. This issue is fixed in versions 24.04.18 and 25.04.11.
- Record
CVE-2026-46499- CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N - Weakness
- CWE-863
- Updated
- 2026-11-05
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| facts | CVE List | |
| first indexed | CVE List, EUVD, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-46499 is a medium vulnerability (CVSS 4.3) in Collaboraonline Online, published October 30, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.25%, the 16th percentile. No source names a fixed version.