CVE-2026-91127: File Viewer: DOM XSS via unsafe hyperlink schemes in the legacy DOC renderer

September 18, 2026

Before 2.3.1, the legacy .doc renderer emitted document hyperlink targets after HTML escaping but without a URL-scheme allowlist. A crafted .doc could therefore render a live javascript:, vbscript:, data:, or similarly unsafe link. Script could execute in the embedding origin if a viewer clicked it.

References

github.com/advisories/GHSA-3753-m2x2-q623
github.com/flyfish-dev/file-viewer/commit/ef045680f8d9830a3eee9612f7df46a734361b07
github.com/flyfish-dev/file-viewer/releases/tag/v2.3.1
github.com/flyfish-dev/file-viewer/security/advisories/GHSA-3753-m2x2-q623
nvd.nist.gov/vuln/detail/CVE-2026-91127

Code Behaviors & Features

Detect and mitigate CVE-2026-91127 with GitLab Dependency Scanning

Secure your software supply chain by verifying that all open source dependencies used in your projects contain no disclosed vulnerabilities. Dependency Scanning using SBOM also detects vulnerabilities from proprietary advisories that this site does not include. Learn more about Dependency Scanning using SBOM →