Safe PDF Viewer: read PDFs in VS Code without running them

Open a PDF in VS Code and know that it cannot act on your machine. The viewer is read-only, loads nothing from the internet, and never runs a document's scripts. Open the file and read it.

A PDF report open in Safe PDF Viewer with a dark VS Code theme, showing a page toolbar, page number, and zoom buttons

Safe by design: PDF files are a long-standing route for malware. This viewer renders every document as untrusted, inside a locked-down panel.
Read-only: it never writes to disk, and there is no editing or form filling to go wrong.
Offline: it makes no network requests of its own. The renderer, Mozilla's PDF.js, ships inside the extension.
Matches your theme: the toolbar and find panel follow your light, dark, or high-contrast VS Code theme.
Nothing to set up: open a .pdf file from the Explorer and it opens in the viewer. There is one setting, for the starting zoom.

Read at your own pace

Turn pages with the arrow keys, PageUp and PageDown, the toolbar buttons, or the scroll wheel. Scrolling past the end of a page turns to the next page. Type in the page number field to jump. Zoom with + and -, or choose Fit Page. The viewer returns to your page and zoom when you switch back to its tab.

The same report zoomed in so that the text fills more of the viewer, in a dark VS Code theme

Find text across the whole document

Press Ctrl+F (Cmd+F on macOS). The find panel counts matches on every page, highlights those on the current page, and steps through them with Enter and Shift+Enter. Escape closes it.

The find panel showing 2 of 6 matches for the word latency, with the matches highlighted on the page in a light theme

Follow links safely

Links inside the document jump to their page. A link to a web address opens in your system browser, but only if it starts with http or https. Links that use javascript:, data:, file: or any other scheme do nothing.

Light and dark

The toolbar and find panel follow the active VS Code color theme.

Dark theme	Light theme

Password-protected files

A protected PDF asks for its password in a masked box. A wrong password prompts again, three prompts in total. The password opens the file once. It is never logged or stored.

Install

VS Code: open the Extensions view (Ctrl+Shift+X or Cmd+Shift+X), search for KunalPathak.safe-pdf-viewer, and select Install.
Cursor, VSCodium, and other forks: install KunalPathak.safe-pdf-viewer from Open VSX.
From a file: download the .vsix from the GitHub releases and run Extensions: Install from VSIX....

Requirements: VS Code at the version in engines.vscode in package.json, or newer. That version is the newest release at least a year old, so most installations qualify.

Use

Open any .pdf file from the Explorer. It opens in the viewer without a command.

Action	Keys
Previous or next page	`←` `→` `↑` `↓`, `PageUp` `PageDown`
Zoom in or out	`+` `-`
Open the find panel	`Ctrl+F` / `Cmd+F`
Next or previous match	`Enter` / `Shift+Enter` in the panel
Close the find panel	`Escape`
Jump to a page	Type in the page number field

The setting safePdfViewer.defaultZoom sets the zoom for newly opened PDFs: fit-page (default), 50, 75, 100, 125, 150 or 200.

What to expect

JPEG 2000 and JBIG2 images show as blank areas. Decoding them needs a looser security policy. decisions.md explains the choice.
A document that uses fonts it does not embed falls back to your system fonts.
A match that spans two text runs, such as a word split by a style change, is counted but not highlighted.
There is no editing, annotation, form filling, printing, or media playback.
It works in Restricted Mode, so PDFs open in workspaces you have not marked as trusted.

Privacy and security

The extension makes no network requests of its own and collects no data. Each layer below limits what a hostile PDF can do.

Layer	What it does
Strict Content Security Policy	A browser rule that blocks everything except the viewer's own script, which carries a fresh random token
No external origins	PDF.js ships inside the extension; the policy allows no other network origin
Scoped file access	The viewer reads only its own PDF.js files and the folder of the open PDF
No document scripts	The scripting engine of PDF.js is not included, and forms stay disabled
Read-only editor	The extension never writes to disk
Link filtering	Only `http` and `https` links open; `javascript:`, `data:` and `file:` are ignored
Passwords	Used once to open the file; never logged or stored

Report vulnerabilities as described in SECURITY.md. The security model is documented in docs/architecture.md.

Contribute

docs/development.md: setup, workflow and release procedure.
docs/testing.md: how each workflow is tested and which checks stay manual.
docs/dependencies.md: version policy and the quarterly review.
docs/architecture.md: design and security model.
docs/workflows.md: the procedure and stopping point for each kind of request.
docs/sibling-extensions.md: the other extensions published as KunalPathak, and the files they share.
docs/decisions.md: ideas not built, and what would reopen them.
AGENTS.md: instructions for coding agents.
CHANGELOG.md: version history.

The project uses the MIT license. The bundled PDF.js carries the Apache License 2.0 in lib/pdfjs/LICENSE.

Safe PDF Viewer

Kunal Pathak