CVE-2026-48164
Published:October 30, 2026
Updated:November 05, 2026
Collabora Online is a collaborative online office suite based on LibreOffice technology. Prior to 24.04.18 and 25.04.11, the "host_session_id" query/form parameter is substituted into the "cool.html" editor page without HTML encoding, unlike parameters passed through the existing variable-encoding mechanism. An attacker who induces a victim to load a crafted URL can inject HTML and, in the absence of an effective "Content Security Policy", execute scripts in the Collabora Online iframe's origin, exposing the session authentication token and page contents. A reverse proxy that preserves the "Content Security Policy" header sent by "coolwsd" mitigates the script-execution scenario. This issue is fixed in versions 24.04.18 and 25.04.11.
Affected Packages
https://gerrit.collaboraoffice.com/online (SCM_GIT):
Affected version(s) >=cp-24.04.4-2 <cp-24.04.18-3Fix Suggestion:
Update to version cp-24.04.18-3https://gerrit.collaboraoffice.com/online (SCM_GIT):
Affected version(s) >=cp-25.04.0-0 <cp-25.04.10-3Fix Suggestion:
Update to version cp-25.04.10-3Related Resources (4)
Do you need more information?
Contact UsCVSS v4
Base Score:
5.3
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
PASSIVE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
LOW
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
LOW
Subsequent System Availability
NONE
CVSS v3
Base Score:
4.7
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
CHANGED
Confidentiality
NONE
Integrity
LOW
Availability
NONE
Weakness Type (CWE)
Improper Neutralization of Input During Web Page Generation
EPSS
Base Score:
0.33