CVE-2026-91127

high

Assigned by CNA: github_m

Published 2026-09-18 · Modified 2026-09-18

Discuss on Community Propose mitigation

CVSS v3

8.2

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N

CVSS v4 NEW

—

not yet in upstream

VIR risk

8.2

Description

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.

Predictions

Exploit likelihood

88%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

Propose a mitigation on Community Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

Package impact

Ecosystem	Package	Vulnerable	Fixed
npm	@file-viewer/doc	`<2.3.1`	`2.3.1`
npm	msdoc-viewer	`<0.2.2`	`0.2.2`

References

CWEs

CWE-79 CWE-83

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.