authority-regex
allows an attacker to send malicious URLs to be parsed by the lambdaisland/uri
and return the wrong authority. This issue is similar to CVE-2020-8910.
https://github.com/lambdaisland/uri/blob/d3355fcd3e235238f4dcd37be97787a84e580072/src/lambdaisland/uri.cljc#L9
This regex doesn't handle the backslash (\
) character in the username correctly, leading to a wrong output.
Payload: https://example.com\\@google.com
The returned host is google.com
, but the correct host should be example.com
.
urllib3
(Python) and google-closure-library
(Javascript) return example.com
as the host. Here the correct (or current) regex used by google-closure-library
:
https://github.com/google/closure-library/blob/0e567abedb058e9b194a40cfa3ad4c507653bccf/closure/goog/uri/utils.js#L189
(ns poc.core)
(require '[lambdaisland.uri :refer (uri)])
(def myurl "https://example.com\\@google.com")
(defn -main
[]
(println myurl)
(println (:host (uri myurl)))
)
The library returns the wrong authority, and it can be abused to bypass host restrictions.
WHATWG Living URL spec, section 4.4 URL Parsing, host state: https://url.spec.whatwg.org/#url-parsing
{ "nvd_published_at": "2023-03-27T21:15:00Z", "github_reviewed_at": "2023-03-27T22:31:13Z", "severity": "MODERATE", "github_reviewed": true, "cwe_ids": [ "CWE-601", "CWE-706" ] }