vulnerability / NVI-00018406 / Revision 1
chi has an open redirect vulnerability in the RedirectSlashes middleware
GitHub lists this reviewed advisory for github.com/go-chi/chi/v5. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
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01 / Meaning
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4.7 medium
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As of · GitHub Advisory Database
02 / Applicability
The affected context
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github.com/go-chi/chi/v5
source listed>= 5.2.2, < 5.2.4
### Summary The `RedirectSlashes` function in middleware/strip.go does not perform correct input validation and can lead to an open redirect vulnerability. ### Details The `RedirectSlashes` function performs a `Trim` to all forward slash (`/`) characters, while prepending a single one at the begining of the path (Line 52). However, it does not trim backslashes (`\`). ```go File: middleware/strip.go 41: func RedirectSlashes(next http.Handler) http.Handler { ... 51: // Trim all leading and trailing slashes (e.g., "//evil.com", "/some/path//") 52: path = "/" + strings.Trim(path, "/") ... 62: } ``` Also, from version 5.2.2 onwards the `RedirectSlashes` function does not take into consideration the `Host` Header in the redirect response returned. This was done in order to combat another vulnerability. The above make it possible for a response in the following form: ``` HTTP/1.1 301 Moved Permanently Location: /\evil.com ``` The `/\evil.com` will be transformed by most browsers (Chrome, Firefox, etc. not Safari) into `//evil.com`
03 / Response
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04 / Limits
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05 / Provenance
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- GHSA-mqqf-5wvp-8fh8 ↗
GitHub Advisory Database · vendor advisory
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- Revision 1 ·
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