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EPSS 0.2%top 88%

webpack-dev-server vulnerable to cross-origin source code exposure on non-HTTPS origins

0
Medium
Published: 05/02/2026 (05/02/2026, 00:00:00 UTC)
Source: GCVE Database
Vendor/Project: Microsoft Security Response Center
Product: Microsoft

Description

CVE-2026-6402 is a vulnerability affecting webpack-dev-server when used on non-HTTPS origins, leading to cross-origin source code exposure. The vulnerability is categorized under CWE-749, which relates to the improper protection of sensitive information. The affected products include Microsoft and Azure Linux versions 3.0. There is no CVSS score provided, and no known exploits in the wild have been reported. No patch or remediation information is currently available from the vendor advisory. The vulnerability could allow unauthorized access to source code when the server is accessed over non-secure (non-HTTPS) connections.

Affected software

Affected versions
=3.0

AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 05/27/2026, 21:29:41 UTC

Technical Analysis

This vulnerability in webpack-dev-server allows cross-origin source code exposure when the server is accessed via non-HTTPS origins. It affects Microsoft and Azure Linux 3.0 versions. The issue is related to improper protection of sensitive information (CWE-749). No CVSS score or patch information is currently available, and no known exploits have been reported. The vendor advisory from Microsoft Security Response Center does not provide remediation details, and the service is not cloud-hosted, so remediation responsibility lies with the user.

Potential Impact

The vulnerability could lead to unauthorized disclosure of source code when webpack-dev-server is used on non-HTTPS origins. This exposure may aid attackers in understanding application internals, potentially facilitating further attacks. However, no known exploits in the wild have been reported, and the overall impact depends on the deployment context and whether non-HTTPS origins are used.

Mitigation Recommendations

Patch status is not yet confirmed — check the Microsoft Security Response Center advisory for current remediation guidance. Until a patch is available, users should avoid running webpack-dev-server on non-HTTPS origins to prevent source code exposure. Using HTTPS for development servers or restricting access to trusted networks may reduce risk.

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Technical Details

Gcve Source
db.gcve.eu
Csaf Category
csaf_vex
Csaf Version
2.0
Publisher
Microsoft Security Response Center
Advisory Id
msrc_CVE-2026-6402
Cve Count
1
Additional Cves
[]
Cvss Version
null

Threat ID: 6a175ef1e29bf47b50ede84b

Added to database: 05/27/2026, 21:15:29 UTC

Last enriched: 05/27/2026, 21:29:41 UTC

Last updated: 07/31/2026, 19:23:00 UTC

Views: 74

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