CVE-2026-14620

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

Workarounds

None

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.

A victim's authenticated browser session is used to submit forged requests to an application that cannot distinguish them from legitimate ones. Typical impact: state-changing actions performed as the victim without their consent.

CVE-2026-14620 has a CVSS score of 4.7 (Medium). The vector is network-reachable, no privileges required, and user interaction required. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (5.2.6); upgrading removes the vulnerable code path.

Kodem intelligence

Already deployed Kodem?

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).

1. What is CVE-2026-14620? CVE-2026-14620 is a medium-severity cross-site request forgery (CSRF) vulnerability in webpack-dev-server (npm), affecting versions <= 5.2.5. It is fixed in 5.2.6. A victim's authenticated browser session is used to submit forged requests to an application that cannot distinguish them from legitimate ones.
2. How severe is CVE-2026-14620? CVE-2026-14620 has a CVSS score of 4.7 (Medium). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of webpack-dev-server are affected by CVE-2026-14620? webpack-dev-server (npm) versions <= 5.2.5 is affected.
4. Is there a fix for CVE-2026-14620? Yes. CVE-2026-14620 is fixed in 5.2.6. Upgrade to this version or later.
5. Is CVE-2026-14620 exploitable, and should I be worried? Whether CVE-2026-14620 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2026-14620 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2026-14620? Upgrade webpack-dev-server to 5.2.6 or later.

Other vulnerabilities in webpack-dev-server