CVE-2026-91127
File Viewer: DOM XSS via unsafe hyperlink schemes in the legacy DOC renderer
- Published
- Updated
- Reserved
- Assigned by
- GitHub_M
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.
Timeline
ID reserved
By GitHub_M
- 4 days later
· 4 days later
Published
- 4 days later
· 4 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| GitHub_MCNA (assigner) | 3.1 | High8.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N |
| NVDNVD · Deferred | 3.1 | High8.2 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.40% · top 66% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 8.2.
Weakness
Affected products
- affected < 2.3.1
- affected < 2.3.1
- affected < 0.2.2
Affected packages
From reviewed advisories of the GitHub Advisory Database.
- npm@file-viewer/docGHSA-3753-m2x2-q623 (opens in a new tab)
- npmmsdoc-viewerGHSA-3753-m2x2-q623 (opens in a new tab)
References (3)
- https://github.com/flyfish-dev/file-viewer/security/advisories/GHSA-3753-m2x2-q623 (opens in a new tab)x_refsource_CONFIRM
- https://github.com/flyfish-dev/file-viewer/commit/ef045680f8d9830a3eee9612f7df46a734361b07 (opens in a new tab)x_refsource_MISC
- https://github.com/flyfish-dev/file-viewer/releases/tag/v2.3.1 (opens in a new tab)x_refsource_MISC
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisory GHSA-3753-m2x2-q623 (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2026-91127)Record last updated .