chi has an open redirect vulnerability in the RedirectSlashes middleware

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

4.7 · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N

EPSS

• CVE-2025-69725: 0.26% estimated exploitation activity in the next 30 days; percentile 17.56 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

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 (\). 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: The /\evil.com will be transformed by most browsers (Chrome, Firefox, etc. not Safari) into //evil.com which is a protocol relative URL and will result in a redirect to evil.com, essentially making it an open redirect vulnerability. PoC A minimal working example can be seen below. And when we request the…

Published by the source

14 Jan 2026, 21:18 UTC

Last modified by the source

18 Jun 2026, 13:02 UTC

Source last checked

26 Oct 2026, 15:24 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-mqqf-5wvp-8fh8

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# Patch Next advisory brief: CVE-2025-69725

Advisory: chi has an open redirect vulnerability in the RedirectSlashes middleware
IDs: CVE-2025-69725, GHSA-mqqf-5wvp-8fh8
Record: https://patchnext.com/advisories/cve-2025-69725 (revision 1, source checked 26 Oct 2026, 15:24 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 4.7)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/go-chi/chi/v5 5.2.4. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/go-chi/chi/v5: affected >= 5.2.2, < 5.2.4; fixed in 5.2.4

## Suggested inspection (read-only)
- Go github.com/go-chi/chi/v5: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/go-chi/chi/v5.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-mqqf-5wvp-8fh8 (GitHub-reviewed advisory GHSA-mqqf-5wvp-8fh8 lists affected ranges: Go github.com/go-chi/chi/v5 >=5.2.2 <5.2.4)

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