CVE-2026-91127

File Viewer is a browser-native viewer for Office, PDF, CAD, archive, and other files in private and internal web applications. Prior to @file-viewer/doc 2.3.1 and msdoc-viewer 0.2.2, the legacy DOC renderer emitted document-controlled hyperlink targets into generated HTML after character escaping but without restricting URL schemes. A crafted legacy DOC file could place javascript:, vbscript:, data:, or another unsafe scheme in a rendered link, and script could execute in the embedding application's origin when a user clicked the link. The fix blocks external document links by default, allows only HTTP(S), mail, telephone, safe relative URLs, and internal bookmarks when external links are explicitly enabled, and applies mount-boundary sanitization as defense in depth. This issue is fixed in @file-viewer/doc 2.3.1 and msdoc-viewer 0.2.2.

CVSS v3 8.2 HIGH

8.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 4.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/flyfish-dev/file-viewer/commit/ef045680f8d9830a3eee9612f7df46a734361b07
https://github.com/flyfish-dev/file-viewer/releases/tag/v2.3.1
https://github.com/flyfish-dev/file-viewer/security/advisories/GHSA-3753-m2x2-q623

Configurations

No configuration.

History

18 Sep 2026, 18:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-18 18:18

Updated : 2026-09-24 21:25

NVD link : CVE-2026-91127

Mitre link : CVE-2026-91127

CVE.ORG link : CVE-2026-91127

JSON object : View

Products Affected

No product.

CWE

CWE-79

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

CWE-83

Improper Neutralization of Script in Attributes in a Web Page

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