{"id":"CVE-2021-23393","details":"This affects the package Flask-Unchained before 0.9.0. When using the the _validate_redirect_url function, it is possible to bypass URL validation and redirect a user to an arbitrary URL by providing multiple back slashes such as \\\\\\evil.com/path. This vulnerability is only exploitable if an alternative WSGI server other than Werkzeug is used, or the default behaviour of Werkzeug is modified using 'autocorrect_location_header=False.","aliases":["GHSA-pjc4-3w99-j7v4","PYSEC-2021-96","SNYK-PYTHON-FLASKUNCHAINED-1293189"],"modified":"2026-07-09T10:52:18.289365Z","published":"2021-06-11T00:15:09.273Z","references":[{"type":"FIX","url":"https://github.com/briancappello/flask-unchained/commit/71e36b28166f9ffbe0a991f51127f0984f7e6a40"},{"type":"FIX","url":"https://snyk.io/vuln/SNYK-PYTHON-FLASKUNCHAINED-1293189"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/briancappello/flask-unchained","events":[{"introduced":"0"},{"fixed":"f282da7b65eb9644cc0d0b1b4c11e74ca04f9dd3"},{"fixed":"71e36b28166f9ffbe0a991f51127f0984f7e6a40"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"0.9.0"}],"source":["CPE_RANGE","REFERENCES"],"cpe":"cpe:2.3:a:flask_unchained_project:flask_unchained:*:*:*:*:*:*:*:*"}}],"versions":["v0.8.1","v0.8.0","v0.7.9","v0.7.8","v0.7.7","v0.7.6","v0.7.5","v0.7.4","v0.7.3","v0.7.2","v0.7.1","v0.7.0","v0.6.6","v0.6.5","v0.6.4","v0.6.3","v0.6.2","v0.6.1","v0.6.0","v0.5.1","v0.5.0","v0.4.2","v0.4.1","v0.4.0","v0.3.2","v0.3.1","v0.2.2","v0.2.1","v0.2.0","v0.1.6","v0.1.5","v0.1.4","v0.1.3","v0.1.2","v0.1.1","v0.1.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-23393.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N"}]}