CVE-2026-76844 evidence review
webpack webpack-dev-middleware
webpack-dev-middleware resolves a request to a local file in getFilenameFromUrl by testing the request pathname against a traversal guard and then slicing it at a fixed character offset. The guard, UP_PATH_REGEXP applied to path.normalize(`./${pathname}`), only matches ".." that stands as a whole path segment, while the containment test is the string comparison pathname.startsWith(publicPathPathname) and the file path is built as path.join(outputPath, pathname.slice(publicPathPathname.length)). When the configured publicPath has no trailing slash, a request such as GET /assets../.env agains...
This record remains available for product and version identification, but it is not presented as a complete remediation procedure. Confirm the affected range and the supported fix in a direct vendor advisory before changing production systems.
Identify the product and installed version
Record whether webpack webpack-dev-middleware is present, where it is installed, and which interfaces are exposed.
- Record the product name, package or appliance identifier, and installed version.
- Identify internet-facing, administrative, API, and internal access paths.
- Preserve the pre-change configuration and relevant service logs.
Compare the affected range
Use the current record as an identification aid: >= 5.3.4 <= 5.3.4, >= 6.1.2 <= 6.1.3, >= 7.1.0 <= 7.4.5, >= 8.0.0 <= 8.1.1. Resolve incomplete inventory results before deciding that an asset is unaffected.
Verify the authoritative remediation source
Open the linked source material and locate a direct vendor advisory for this CVE. Confirm the supported fixed release and product-specific update path before making a production change.
Operational boundary
This page does not replace the vendor advisory, support contract, change-management process, or recovery plan. Do not infer that an asset is unaffected from an incomplete inventory query or a missing fixed-version field.