CVE-2022-23527: Open Redirect in oidc_validate_redirect_url()
modauthopenidc is an OpenID Certified™ authentication and authorization module for the Apache 2.x HTTP server. Versions prior to 2.4.12.2 are vulnerable to Open Redirect. When providing a logout parameter to the redirect URI, the existing code in oidcvalidateredirecturl() does not properly check for URLs that start with /\t, leading to an open redirect. This issue has been patched in version 2.4.12.2. Users unable to upgrade can mitigate the issue by configuring modauthopenidc to only allow redirection when the destination matches a given regular expression with OIDCRedirectURLsAllowed.
Affected Software
Event History
Frequently Asked Questions
What is CVE-2022-23527?
CVE-2022-23527 is a vulnerability in the mod_auth_openidc module for Apache 2.x that allows for Open Redirect attacks.
What versions of mod_auth_openidc are affected by CVE-2022-23527?
Versions prior to 2.4.12.2 of mod_auth_openidc are affected by CVE-2022-23527.
What is the severity of CVE-2022-23527?
CVE-2022-23527 has a severity rating of 6.1 (Medium).
How does CVE-2022-23527 work?
CVE-2022-23527 works by not properly checking the logout parameter in the redirect URI, allowing for Open Redirect attacks.
How can I fix CVE-2022-23527?
To fix CVE-2022-23527, update mod_auth_openidc to version 2.4.12.2 or later.