CVE-2026-9595

Published: Giu 15, 2026 Last Modified: Giu 16, 2026
ExploitDB:
Other exploit source:
Google Dorks:
MEDIUM 5,3
Source: ce714d77-add3-4f53-aff5-83d477b104bb
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: none
Scope: unchanged
Confidentiality: none
Integrity: none
Availability: low

Description

AI Translation Available

Impact: When a user-configured proxy on webpack-dev-server has a broad context (e.g. /) and ws: true, it also intercepts the dev server's own HMR WebSocket and forwards it to the proxy target. This leaks the browser's cookies and Origin header to the backend, bypasses the dev server's Host/Origin validation, and corrupts the HMR socket (both HMR and the proxy end up writing to the same socket).

Patches: Fixed in [email protected].

Workarounds: Scope user-defined proxy context to specific paths instead of /, or omit ws: true from the proxy entry when WebSocket forwarding is not required.

EPSS (Exploit Prediction Scoring System)

Trend Analysis

EPSS (Exploit Prediction Scoring System)

Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.

EPSS Score
0,0020
Percentile
0,1th
Updated

EPSS Score Trend (Last 2 Days)

346

Origin Validation Error

Draft
Abstraction: Class Structure: Simple
Common Consequences
Security Scopes Affected:
Access Control Other
Potential Impacts:
Gain Privileges Or Assume Identity Varies By Context
Applicable Platforms
Technologies: Not Technology-Specific, Web Based
View CWE Details
441

Unintended Proxy or Intermediary ('Confused Deputy')

Draft
Abstraction: Class Structure: Simple
Common Consequences
Security Scopes Affected:
Non-Repudiation Access Control
Potential Impacts:
Gain Privileges Or Assume Identity Hide Activities Execute Unauthorized Code Or Commands
Applicable Platforms
All platforms may be affected
View CWE Details
Application

Webpack-Dev-Server by Webpack.Js

Product Information
Vendor Webpack.Js
Product Webpack-Dev-Server
Version Range Affected
To 5.2.5 (exclusive)
cpe:2.3:a:webpack.js:webpack-dev-server:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
https://cna.openjsf.org/security-advisories.html
https://cna.openjsf.org/security-advisories.html
https://github.com/facebook/create-react-app/pull/7444
https://github.com/facebook/create-react-app/pull/7444
https://github.com/vuejs/vue-cli/commit/72ba7505aff2a8314e8…
https://github.com/vuejs/vue-cli/commit/72ba7505aff2a8314e82aa5082379a77504a1fcb
https://github.com/webpack/webpack-dev-server/pull/4316
https://github.com/webpack/webpack-dev-server/pull/4316
https://github.com/webpack/webpack-dev-server/security/advi…
https://github.com/webpack/webpack-dev-server/security/advisories/GHSA-mx8g-39q…