Same Origin Policy bypass via Origin reflection
Published Dec 27, 2022 · Updated Apr 11, 2025
Origin validation errors in Gorilla Handlers before 1.3.0 allow remote attackers to bypass the Same Origin Policy through CORS requests. cors.ServeHTTP copies the request's Origin value into Access-Control-Allow-Origin even when allowedOrigins contains the wildcard entry. Exposure requires an application to use the CORS middleware with that policy, causing the response to authorize the requester's origin instead of returning a literal wildcard.
Summary
What happened
Origin validation errors in Gorilla Handlers before 1.3.0 allow remote attackers to bypass the Same Origin Policy through CORS requests. cors.ServeHTTP copies the request's Origin value into Access-Control-Allow-Origin even when allowedOrigins contains the wildcard entry. Exposure requires an application to use the CORS middleware with that policy, causing the response to authorize the requester's origin instead of returning a literal wildcard.
The record
- CVE
- CVE-2017-20146
- Published
- Dec 27, 2022
- Updated
- Apr 11, 2025
- Vendor
- Gorilla Web Toolkit
- Product
- Gorilla Handlers
- Classifications
- CWE-346
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Dec 27, 2022CVE publishedPublication date reported by the CVE source.
- Apr 11, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=0 <1.3.0
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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