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CVE-2025-62379 Detail

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.


Metrics

NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://github.com/reflex-dev/reflex/commit/ade12549f3c0ddab3d7382c581bc04a3c1f989ec GitHub, Inc.
https://github.com/reflex-dev/reflex/security/advisories/GHSA-rfh5-c9h5-q8jm GitHub, Inc.

Weakness Enumeration

CWE-ID CWE Name Source
CWE-601 URL Redirection to Untrusted Site ('Open Redirect') GitHub, Inc.  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-62379
NVD Published Date:
10/15/2025
NVD Last Modified:
10/15/2025
Source:
GitHub, Inc.