CVE-2026-48164

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.

CVSS v3 4.7 MEDIUM

4.7^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/CollaboraOnline/online/commit/2d4469d27f0c52f4b28b64090e60452d2e147279
https://github.com/CollaboraOnline/online/security/advisories/GHSA-wgmm-q3ch-64jj

Configurations

No configuration.

History

30 Oct 2026, 15:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-30 15:16

Updated : 2026-10-30 19:37

NVD link : CVE-2026-48164

Mitre link : CVE-2026-48164

CVE.ORG link : CVE-2026-48164

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

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