CVE-2026-14620: 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
Other sources
webpack-dev-server versions 5.2.5 and earlier expose two internal developer endpoints, /webpack-dev-server/open-editor and /webpack-dev-server/invalidate, that 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 these endpoints 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, and repeated requests can spawn editor processes and force recompilations that degrade the developer's machine. Patches: upgrade to webpack-dev-server 5.2.6. Workarounds: none.
— MITRE
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
npm/webpack-dev-serverto a version that resolves this vulnerability.Fixed in 5.2.6 - Upgrade
Upgrade
webpack-dev-serverto a version that resolves this vulnerability.Fixed in 5.2.6Patch PR #5698
Event History
Frequently Asked Questions
What is the severity of CVE-2026-14620?
CVE-2026-14620 has a medium severity rating of 4.7.
How do I fix CVE-2026-14620?
To fix CVE-2026-14620, upgrade to webpack-dev-server version 5.2.6 or later.
What types of attacks are possible with CVE-2026-14620?
CVE-2026-14620 allows for cross-site request forgery (CSRF) attacks via vulnerable internal developer endpoints.
Which versions of webpack-dev-server are affected by CVE-2026-14620?
webpack-dev-server versions 5.2.5 and earlier are affected by CVE-2026-14620.
What are the vulnerable endpoints in CVE-2026-14620?
CVE-2026-14620 exposes the /webpack-dev-server/open-editor and /webpack-dev-server/invalidate endpoints without proper request verification.