CVE-2021-41263: Secure/signed cookies share secrets between sites in rails_multisite
railsmultisite provides multi-db support for Rails applications. In affected versions this vulnerability impacts any Rails applications using railsmultisite alongside Rails' signed/encrypted cookies. Depending on how the application makes use of these cookies, it may be possible for an attacker to re-use cookies on different 'sites' within a multi-site Rails application. The issue has been patched in v4 of the railsmultisite gem. Note that this upgrade will invalidate all previous signed/encrypted cookies. The impact of this invalidation will vary based on the application architecture.
Affected Software
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Event History
Frequently Asked Questions
What is the severity of CVE-2021-41263?
CVE-2021-41263 has medium severity as it affects Rails applications using `rails_multisite` with potential impacts on signed/encrypted cookies.
How do I fix CVE-2021-41263?
To fix CVE-2021-41263, update the `rails_multisite` gem to version 4.0.0 or later.
Which versions of rails_multisite are affected by CVE-2021-41263?
CVE-2021-41263 affects all versions of `rails_multisite` prior to 4.0.0.
What applications are impacted by CVE-2021-41263?
Any Rails applications utilizing `rails_multisite` combined with signed/encrypted cookies are impacted by CVE-2021-41263.
Is CVE-2021-41263 exploitable?
Yes, depending on the application's use of cookies, CVE-2021-41263 may be exploitable.