🚨 [security] Update webpack-dev-server 5.2.4 → 5.2.6 (patch)

[depfu]

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🚨 Your current dependencies have known security vulnerabilities 🚨

This dependency update fixes known security vulnerabilities. Please see the details below and assess their impact carefully. We recommend to merge and deploy this as soon as possible!

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Here is everything you need to know about this update. Please take a good look at what changed and the test results before merging this pull request.

What changed?

✳️ webpack-dev-server (5.2.4 → 5.2.6) · Repo · Changelog

Security Advisories 🚨

🚨 webpack-dev-server vulnerable to denial of service via a malformed Host or Origin header

Impact

An unauthenticated peer that can reach the webpack-dev-server process can terminate it by sending either a normal HTTP request with a malformed Host header, or a WebSocket upgrade to the default /ws endpoint with a malformed Origin header. The malformed header triggers an uncaught exception in the host-validation path and crashes the dev server process.

Patches

Fixed in webpack-dev-server 5.2.6 by treating malformed Host and Origin header values as invalid rather than throwing (see PR #5699).

Workarounds

Keep the dev server bound to localhost (the default) and do not expose it to untrusted networks.

🚨 webpack-dev-server vulnerable to cross-site request forgery via internal developer endpoints

Impact

The internal /webpack-dev-server/open-editor and /webpack-dev-server/invalidate endpoints perform state-changing actions on any GET request, without verifying that the request originated from the dev server's own page. Any website a developer visits while the dev server is running can trigger them cross-origin with no interaction beyond the visit.

An attacker can open an arbitrary existing local file in the developer's editor, including files outside the project root (e.g. ~/.ssh/config). The file's contents are not returned to the attacker. Repeated requests can also spawn editor processes and force recompilations, degrading the developer's machine.

Patches

Fixed in webpack-dev-server 5.2.6 by rejecting cross-site requests to the /webpack-dev-server/open-editor and /webpack-dev-server/invalidate endpoints (see PR #5698).

Workarounds

None

🚨 webpack-dev-server vulnerable to HMR WebSocket interception via permissive user proxies

Impact

When a user-configured proxy on webpack-dev-server has a broad context (e.g. /) and ws: true, it also intercepts the dev server's own HMR WebSocket and forwards it to the proxy target. This leaks the browser's cookies and Origin header to the backend, bypasses the dev server's Host/Origin validation, and corrupts the HMR socket (both HMR and the proxy end up writing to the same socket).

Patches

Fixed in webpack-dev-server 5.2.5.

Workarounds

Scope user-defined proxy context to specific paths instead of /, or omit ws: true from the proxy entry when WebSocket forwarding is not required.

Release Notes

5.2.6

Patch Changes

• fix: allow undefined as the Server constructor options argument again (by @bjohansebas in #5695)

  Restores accepting undefined (defaulting it to {}) for the options
  argument, so passing a webpack config's optional devServer field type-checks and works as before.

• Protect the built-in state-changing routes (/webpack-dev-server/invalidate and /webpack-dev-server/open-editor) against cross-site request forgery. Requests are now checked with Sec-Fetch-Site (falling back to an Origin/Host comparison when it is absent), so a cross-site page can no longer trigger a rebuild or open a file in the editor. Same-origin requests, user-initiated navigations, and non-browser clients (e.g. curl) are unaffected. (by @bjohansebas in #5698)

• Handle malformed Host and Origin header values gracefully when validating requests. (by @bjohansebas in #5699)

5.2.5

Patch Changes

• Skip the HMR WebSocket path when forwarding upgrade requests to user-defined proxies, so custom proxy WebSocket upgrades are no longer intercepted by the dev server. (by @bjohansebas in #5680)

Does any of this look wrong? Please let us know.

Commits

See the full diff on Github. The new version differs by 10 commits:

• chore(release): new release (#5697)
• fix: handle malformed Host and Origin headers (#5699)
• fix: reject cross-site requests to open-editor and invalidate endpoints (#5698)
• fix: handle undefined options in Server constructor (#5695)
• chore: update branch references from v4 to v5 in workflow configuration
• chore: add v5 branch to release workflow triggers
• chore(release): new release (#5682)
• feat: add changeset validation and release workflow (#5680)
• fix(proxy): match the HMR upgrade path exactly like the ws server (#5678)
• fix: skip HMR websocket path when forwarding upgrades to user-defined proxies (#4316)

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[socket-security]

Review the following changes in direct dependencies. Learn more about Socket for GitHub.

Diff	Package	Supply Chain Security	Vulnerability	Quality	Maintenance	License
	webpack-dev-server@​5.2.4 ⏵ 5.2.6		+4		+2

View full report