Description
Webpack is a module bundler. From version 5.49.0 to before 5.104.1, when experiments.buildHttp is enabled, webpack’s HTTP(S) resolver (HttpUriPlugin) can be bypassed to fetch resources from hosts outside allowedUris by using crafted URLs that include userinfo (username:password@host). If allowedUris enforcement relies on a raw string prefix check (e.g., uri.startsWith(allowed)), a URL that looks allow-listed can pass validation while the actual network request is sent to a different authority/host after URL parsing. This is a policy/allow-list bypass that enables build-time SSRF behavior (outbound requests from the build machine to internal-only endpoints, depending on network access) and untrusted content inclusion (the fetched response is treated as module source and bundled). This issue has been patched in version 5.104.1.
CVSS Metrics
- Vector
- CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:N
- Attack Vector
- network
- Complexity
- high
- Privileges
- low
- User Action
- required
- Scope
- unchanged
- Confidentiality
- low
- Integrity
- low
- Availability
- none
- Weaknesses
- CWE-918
Metadata
- Primary Vendor
- UNKNOWN
- Published
- 2/5/2026
- Last Modified
- 2/6/2026
- Source
- NIST NVD
- Note: Verify all details with official vendor sources before applying patches.
Affected Products
No affected products information available.
AI-Powered Remediation
Generate remediation guidance or a C-suite brief for this vulnerability.