{"id":"CVE-2026-122132","aliases":["DEBIAN-CVE-2026-122132","EUVD-2026-117086","GHSA-27h9-x5w9-37mx","GHSA-mqqf-5wvp-8fh8","GO-2026-4316","UBUNTU-CVE-2026-122132"],"status":"published","title":"go-chi chi 5.2.2 through 5.5.0 Open Redirect via RedirectSlashes Middleware","description":"go-chi chi 5.2.2 through 5.5.0 contains an open redirect vulnerability in the RedirectSlashes middleware that allows attackers to redirect victims to external hosts by embedding tab characters in request paths. Attackers can craft links with a URL-encoded tab, which browsers strip from the 301 Location header and resolve as a protocol-relative URL, bypassing the fix for CVE-2025-69725.","severity":{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-12","score":0.00269,"percentile":0.19333,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-601"],"published":"2026-01-14T21:18:06Z","modified":"2026-11-06T01:00:19Z","affected":[{"source":"osv","ecosystem":"Debian:14","package":"golang-github-go-chi-chi","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.2.0-1","5.2.3-1","5.2.5-1","5.3.0-1"]},{"source":"osv","ecosystem":"Go","package":"github.com/go-chi/chi/v5","ranges":[{"type":"SEMVER","events":[{"introduced":"5.2.2"},{"fixed":"5.2.4"}]}],"bundled":2},{"source":"osv","ecosystem":"Go","package":"github.com/go-chi/chi","ranges":[{"type":"SEMVER","events":[{"introduced":"0"}]}],"bundled":2},{"source":"osv","ecosystem":"Go","package":"github.com/go-chi/chi/v2","ranges":[{"type":"SEMVER","events":[{"introduced":"0"}]}],"bundled":2},{"source":"osv","ecosystem":"Go","package":"github.com/go-chi/chi/v3","ranges":[{"type":"SEMVER","events":[{"introduced":"0"}]}],"bundled":2},{"source":"osv","ecosystem":"Go","package":"github.com/go-chi/chi/v4","ranges":[{"type":"SEMVER","events":[{"introduced":"0"}]}],"bundled":2},{"source":"osv","ecosystem":"Go","package":"github.com/go-chi/chi/v5","ranges":[{"type":"SEMVER","events":[{"introduced":"5.2.2"},{"fixed":"5.2.4"}]}],"bundled":2},{"source":"osv","ecosystem":"Ubuntu:22.04:LTS","package":"golang-github-go-chi-chi","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.5.1-2","5.0.7-1"]},{"source":"osv","ecosystem":"Ubuntu:24.04:LTS","package":"golang-github-go-chi-chi","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.0.7-1"]},{"source":"osv","ecosystem":"Ubuntu:26.10","package":"golang-github-go-chi-chi","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.2.3-1","5.3.0-1"]},{"source":"osv","ecosystem":"Ubuntu:26.04:LTS","package":"golang-github-go-chi-chi","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["5.2.0-1","5.2.3-1"]}],"products":[{"vendor":"go-chi","product":"chi"}],"references":[{"url":"https://github.com/go-chi/chi/pull/1238","tags":["issue-tracking","patch","fix","report"]},{"url":"https://github.com/go-chi/chi","tags":["product","package","report"]},{"url":"https://github.com/go-chi/chi/security/advisories/GHSA-mqqf-5wvp-8fh8","tags":["related","vendor-advisory","exploit","advisory","web","report"]},{"url":"https://github.com/go-chi/chi/blob/v5.5.0/middleware/strip.go#L41-L69","tags":["technical-description","article","report"]},{"url":"https://www.vulncheck.com/advisories/go-chi-chi-5.2.2-through-5.5.0-open-redirect-via-redirectslashes-middleware","tags":["third-party-advisory","advisory","report"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-122132","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-27h9-x5w9-37mx"},{"url":"http://go-chichi.com","tags":["web"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/122xxx/CVE-2026-122132.json","tags":["advisory"]},{"url":"https://security-tracker.debian.org/tracker/CVE-2026-122132","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-69725","tags":["advisory"]},{"url":"https://github.com/go-chi/chi/issues/1037","tags":["web","report"]},{"url":"https://github.com/go-chi/chi/commit/6eb35881c0e438ffb663ddbad3a61babaa5e5d8a","tags":["web","fix"]},{"url":"https://ubuntu.com/security/CVE-2026-122132","tags":["report"]},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-122132","tags":["report"]}],"sources":{"cve":[{"id":"CVE-2026-122132","title":"go-chi chi 5.2.2 through 5.5.0 Open Redirect via RedirectSlashes Middleware","description":"go-chi chi 5.2.2 through 5.5.0 contains an open redirect vulnerability in the RedirectSlashes middleware that allows attackers to redirect victims to external hosts by embedding tab characters in request paths. Attackers can craft links with a URL-encoded tab, which browsers strip from the 301 Location header and resolve as a protocol-relative URL, bypassing the fix for CVE-2025-69725.","status":"published","published":"2026-11-04T20:36:51.758Z","modified":"2026-11-05T19:41:43.032Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","level":"medium","assessor":"cna"},{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"cna"}],"cwes":["CWE-601"],"updated_at":"2026-11-05T20:54:59.423743Z"}],"euvd":[{"id":"EUVD-2026-117086","description":"go-chi chi 5.2.2 through 5.5.0 contains an open redirect vulnerability in the RedirectSlashes middleware that allows attackers to redirect victims to external hosts by embedding tab characters in request paths. Attackers can craft links with a URL-encoded tab, which browsers strip from the 301 Location header and resolve as a protocol-relative URL, bypassing the fix for CVE-2025-69725.","status":"published","published":"2026-11-04T20:36:51Z","modified":"2026-11-05T19:41:43Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-05T21:01:59.785126Z"}],"ghsa":[{"id":"GHSA-27h9-x5w9-37mx","title":"go-chi chi 5.2.2 through 5.5.0 contains an open redirect vulnerability in the RedirectSlashes...","description":"go-chi chi 5.2.2 through 5.5.0 contains an open redirect vulnerability in the RedirectSlashes middleware that allows attackers to redirect victims to external hosts by embedding tab characters in request paths. Attackers can craft links with a URL-encoded tab, which browsers strip from the 301 Location header and resolve as a protocol-relative URL, bypassing the fix for CVE-2025-69725.","status":"published","published":"2026-11-04T21:32:31Z","modified":"2026-11-04T21:32:40Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium"},{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium"}],"cwes":["CWE-601"],"updated_at":"2026-11-04T21:42:46.194147Z"}],"nvd":[{"id":"CVE-2026-122132","description":"go-chi chi 5.2.2 through 5.5.0 contains an open redirect vulnerability in the RedirectSlashes middleware that allows attackers to redirect victims to external hosts by embedding tab characters in request paths. Attackers can craft links with a URL-encoded tab, which browsers strip from the 301 Location header and resolve as a protocol-relative URL, bypassing the fix for CVE-2025-69725.","status":"published","published":"2026-11-04T21:18:08.89Z","modified":"2026-11-05T20:17:49.99Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium","assessor":"secondary"},{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium","assessor":"secondary"}],"cwes":["CWE-601"],"updated_at":"2026-11-05T21:56:49.714113Z"}],"osv":[{"id":"CVE-2025-69725","description":"An Open Redirect vulnerability in the go-chi/chi \u003e=5.2.2 RedirectSlashes function allows remote attackers to redirect victim users to malicious websites using the legitimate website domain.","status":"published","published":"2026-02-19T17:24:39.83Z","modified":"2026-11-05T10:55:55.386587623Z","cvss":[{"version":"3.1","score":4.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N","level":"medium"}],"updated_at":"2026-11-05T13:30:49.23793Z"},{"id":"CVE-2026-122132","title":"go-chi chi 5.2.2 through 5.5.0 Open Redirect via RedirectSlashes Middleware","description":"go-chi chi 5.2.2 through 5.5.0 contains an open redirect vulnerability in the RedirectSlashes middleware that allows attackers to redirect victims to external hosts by embedding tab characters in request paths. Attackers can craft links with a URL-encoded tab, which browsers strip from the 301 Location header and resolve as a protocol-relative URL, bypassing the fix for CVE-2025-69725.","status":"published","published":"2026-11-04T20:36:51.758Z","modified":"2026-11-07T02:30:43.02569382Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"cwes":["CWE-601"],"updated_at":"2026-11-07T03:08:01.726202Z"},{"id":"DEBIAN-CVE-2026-122132","description":"go-chi chi 5.2.2 through 5.5.0 contains an open redirect vulnerability in the RedirectSlashes middleware that allows attackers to redirect victims to external hosts by embedding tab characters in request paths. Attackers can craft links with a URL-encoded tab, which browsers strip from the 301 Location header and resolve as a protocol-relative URL, bypassing the fix for CVE-2025-69725.","status":"published","published":"2026-11-04T21:18:08.89Z","modified":"2026-11-06T17:29:22.662038652Z","cvss":[{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"medium"}],"updated_at":"2026-11-06T18:00:26.717991Z"},{"id":"GHSA-mqqf-5wvp-8fh8","title":"chi has an open redirect vulnerability in the RedirectSlashes middleware","description":"### Summary\n\nThe `RedirectSlashes` function in middleware/strip.go does not perform correct input validation and can lead to an open redirect vulnerability.\n\n### Details\n\nThe `RedirectSlashes` function performs a `Trim` to all forward slash (`/`) characters, while prepending a single one at the begining of the path (Line 52).\n\nHowever, it does not trim backslashes (`\\`).\n\n```go\nFile: middleware/strip.go\n41: func RedirectSlashes(next http.Handler) http.Handler {\n...\n51: \t\t\t// Trim all leading and trailing slashes (e.g., \"//evil.com\", \"/some/path//\")\n52: \t\t\tpath = \"/\" + strings.Trim(path, \"/\")\n...\n62: }\n```\n\nAlso, 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](https://github.com/go-chi/chi/security/advisories/GHSA-vrw8-fxc6-2r93)](https://github.com/go-chi/chi/security/advisories/GHSA-vrw8-fxc6-2r93).\n\nThe above make it possible for a response in the following form:\n\n```\nHTTP/1.1 301 Moved Permanently\nLocation: /\\evil.com\n```\n\nThe `/\\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.\n\n### PoC\n\nA minimal working example can be seen below.\n\n```go\npackage main\n\nimport (\n\t\"fmt\"\n\t\"net/http\"\n\n\t\"github.com/go-chi/chi/v5\"\n\t\"github.com/go-chi/chi/v5/middleware\"\n)\n\n\n\nfunc main() {\n\tr := chi.NewRouter()\n\n\tr.Use(middleware.RedirectSlashes)\n\n\tr.Get(\"/*\", func(w http.ResponseWriter, r *http.Request) {\n\t\tw.WriteHeader(http.StatusOK)\n\t})\n\n\tfmt.Println(\"Server starting on port 8081...\")\n\tif err := http.ListenAndServe(\":8081\", r); err != nil {\n\t\tfmt.Printf(\"Error starting server: %v\\n\", err)\n\t}\n}\n\n```\n\nAnd when we request the path `/\\evil.com` (needs a second backslash or URL encoding in the terminal), the HTTP Redirect Location is just `/\\evil.com` without any domain/Host information.\n\n```bash\n$ curl -I  localhost:8081/\\\\evil.com/\nHTTP/1.1 301 Moved Permanently\nContent-Type: text/html; charset=utf-8\nLocation: /\\evil.com\n```\n\n```bash\n$ curl -I  localhost:8081/%5Cevil.com/\nHTTP/1.1 301 Moved Permanently\nContent-Type: text/html; charset=utf-8\nLocation: /\\evil.com\n```\n\nThis opened in a browser (Chrome, Firefox) will result in a transformation to `//evil.com` which in turn will result in a redirect to `evil.com`.\n\u003cimg width=\"200\" alt=\"image-20250829115619807\" src=\"https://github.com/user-attachments/assets/44aedad1-64b6-4660-8b26-fad9b4eca036\" /\u003e\n\n\n\u003cimg width=\"200\" alt=\"image-20250829115632067\" src=\"https://github.com/user-attachments/assets/b976d47d-1975-469c-abd3-deb907a68db2\" /\u003e\n\n\n### Impact\n\nThis essentially consists of an open redirect vulnerability, provided that victim users use the most popular browsers (Chrome, Firefox, etc. It does not work in e.g. Safari).\n\nThe attacker can construct a malicious URL on a domain of a legitimate website and send it to the victim user. The victim users thinking that they will click on a legitimate website's URL, they will unknowingly be reidrected to an attacker controlled website.\n\nThis can lead to credential theft if the victim gets redirected to a phishing website, to malware that is hosted on the attacker controlled website etc. Also, it has a greate reputation / business impact for the affected legitimate website.\n\nIn order to exploit this vulnerability the attacker does not need to be authenticated or have ay other priviledge / knowledge regarding the affected application.\n\nCVSS Score: [4.7 (Medium)](https://www.first.org/cvss/calculator/3-0#CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N)","status":"published","published":"2026-01-14T21:18:06Z","modified":"2026-11-05T10:55:55.386587623Z","cvss":[{"version":"3.1","score":4.7,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N","level":"medium"}],"cwes":["CWE-601"],"updated_at":"2026-11-05T13:30:49.23793Z"},{"id":"UBUNTU-CVE-2026-122132","description":"go-chi chi 5.2.2 through 5.5.0 contains an open redirect vulnerability in the RedirectSlashes middleware that allows attackers to redirect victims to external hosts by embedding tab characters in request paths. Attackers can craft links with a URL-encoded tab, which browsers strip from the 301 Location header and resolve as a protocol-relative URL, bypassing the fix for CVE-2025-69725.","status":"published","published":"2026-11-05T00:00:00Z","modified":"2026-11-06T01:00:19.973912145Z","cvss":[{"version":"3.1","score":6.1,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","level":"medium"},{"version":"4.0","score":5.1,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N","level":"medium"}],"updated_at":"2026-11-06T01:33:05.666804Z"},{"id":"GO-2026-4316","title":"Open redirect vulnerability in the RedirectSlashes middleware in github.com/go-chi/chi","description":"Open redirect vulnerability in the RedirectSlashes middleware in github.com/go-chi/chi","status":"published","published":"2026-01-23T02:28:11Z","modified":"2026-11-05T10:55:55.386587623Z","updated_at":"2026-11-05T13:30:49.23793Z"}]}}