@acastellon/auth is an authentication control system for microservices. Versions prior to 2.3.0 appear to allow an unauthenticated authentication bypass in validateToken() through spoofable auth-user and Host request headers. The validateToken middleware contains a service-to-service bypass for auth-user: service-brother when req.get('host').startsWith(getHostName()). Both values involved in the check can be influenced by an unauthenticated HTTP client: auth-user is a request header, and Host is also client-controlled. As a result, a remote unauthenticated attacker can send a request with crafted headers and bypass token validation before the normal legacy/JWT/OIDC validation logic runs. A fix has been implemented in v2.3.0.
Metrics
Affected Vendors & Products
References
History
Mon, 06 Jul 2026 23:15:00 +0000
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Antonio-castellon
Antonio-castellon module-auth |
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| Vendors & Products |
Antonio-castellon
Antonio-castellon module-auth |
Thu, 02 Jul 2026 15:30:00 +0000
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ssvc
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Wed, 01 Jul 2026 14:30:00 +0000
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| Description | @acastellon/auth is an authentication control system for microservices. Versions prior to 2.3.0 appear to allow an unauthenticated authentication bypass in validateToken() through spoofable auth-user and Host request headers. The validateToken middleware contains a service-to-service bypass for auth-user: service-brother when req.get('host').startsWith(getHostName()). Both values involved in the check can be influenced by an unauthenticated HTTP client: auth-user is a request header, and Host is also client-controlled. As a result, a remote unauthenticated attacker can send a request with crafted headers and bypass token validation before the normal legacy/JWT/OIDC validation logic runs. A fix has been implemented in v2.3.0. | |
| Title | @acastellon/auth has an authentication bypass via spoofable headers in validateToken() | |
| Weaknesses | CWE-287 | |
| References |
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| Metrics |
cvssV4_0
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Status: PUBLISHED
Assigner: GitHub_M
Published: 2026-07-01T14:25:44.452Z
Updated: 2026-07-02T14:26:00.684Z
Reserved: 2026-06-30T18:19:58.378Z
Link: CVE-2026-58399
Updated: 2026-07-02T14:25:57.146Z
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