Description
webpack-dev-server versions up to and including 5.2.3 are vulnerable to cross-origin source code exposure when serving over a non-potentially trustworthy origin such as plain HTTP. The previous fix relied on the Sec-Fetch-Mode and Sec-Fetch-Site request headers, which browsers omit for non-trustworthy origins, allowing a malicious site to load the bundled source as a script and read it across origins. Impact: an attacker controlling a website visited by a developer running webpack-dev-server can recover the application source code when the dev server runs over HTTP at a guessable host and port. Chromium based browsers from Chrome 142 onward are not affected due to local network access restrictions. Upgrade to webpack-dev-server 5.2.4 or later, which sets Cross-Origin-Resource-Policy: same-origin on responses.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| webpack-dev-server | webpack-dev-server | < 5.2.4 | 5.2.4 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | agama-web-ui | 21+360.16caae772-44.1 | openSUSE-SU-2026:10979-1 |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | katib-earlystopping +8 | 0.19.0-r31 | — |
| Wolfi rolling | katib-suggestion-goptuna-compat | 0.19.0-r40 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| npm | webpack-dev-server | < 5.2.4 | 5.2.4 | GHSA-79cf-xcqc-c78w |
Advisories 1
- openSUSE-SU-2026:10979-1 agama-web-ui-21+360.16caae772-44.1 on GA media SUSE / openSUSE Security Updates · Jun 10, 2026