{"cve":"CVE-2025-62379","nvd":{"published":"2025-10-15T16:15:36.357","modified":"2026-10-19T16:10:00.260","status":"Deferred","description":"Reflex is a library to build full-stack web apps in pure Python. In versions 0.5.4 through 0.8.14, the /auth-codespace endpoint automatically assigns the redirect_to query parameter value directly to client-side links without any validation and triggers automatic clicks when the page loads in a GitHub Codespaces environment. This allows attackers to redirect users to arbitrary external URLs. The vulnerable route is only registered when a Codespaces environment is detected, and the detection is controlled by environment variables. The same behavior can be activated in production if the GITHUB_CODESPACES_PORT_FORWARDING_DOMAIN environment variable is set. The vulnerability occurs because the code assigns the redirect_to query parameter directly to a.href without any validation and immediately triggers a click (automatic navigation), allowing users to be sent to arbitrary external domains. The execution condition is based on the presence of a sessionStorage flag, meaning it triggers immediately on first visits or in incognito/private browsing windows, with no server-side origin/scheme whitelist or internal path enforcement defenses in place. This issue has been patched in version 0.8.15. As a workaround, users can ensure that GITHUB_CODESPACES_PORT_FORWARDING_DOMAIN is not set in a production environment.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:L/A:N","score":3.1},"cwes":["CWE-601"],"references":["https://github.com/reflex-dev/reflex/commit/ade12549f3c0ddab3d7382c581bc04a3c1f989ec","https://github.com/reflex-dev/reflex/security/advisories/GHSA-rfh5-c9h5-q8jm"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:12:35.277909958+00:00"},"epss":{"cve":"CVE-2025-62379","score":0.00253,"percentile":0.16651,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-rfh5-c9h5-q8jm","url":"https://osv.dev/vulnerability/GHSA-rfh5-c9h5-q8jm","summary":"reflex-dev/reflex has an Open Redirect vulnerability","modified":"2026-07-07T17:56:21.739218136Z","packages":[{"ecosystem":"PyPI","name":"reflex","purl":"pkg:pypi/reflex","ranges":[">=0.5.4 <=0.8.14"],"fixed":[]}]},{"id":"PYSEC-2026-1868","url":"https://osv.dev/vulnerability/PYSEC-2026-1868","summary":"reflex-dev/reflex has an Open Redirect vulnerability","modified":"2026-07-07T17:47:00.306257423Z","packages":[{"ecosystem":"PyPI","name":"reflex","purl":"pkg:pypi/reflex","ranges":[">=0.5.4 <=0.8.14"],"fixed":[]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}