Information disclosure in Discourse Rails Multisite

CVE-2021-41263

rails_multisite provides multi-db support for Rails applications. In affected versions this vulnerability impacts any Rails applications using `rails_multisite` 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 `rails_multisite` gem. Note that this upgrade will invalidate all previous signed/encrypted cookies. The impact of this invalidation will vary based on the application architecture.

Vulnerability class: Information Disclosure

EPSS: 0.006 (45.6th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.3 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:L/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-41263?
CVE-2021-41263 is a high-severity vulnerability in Discourse Rails Multisite, classified under Information Disclosure. CVSS score: 8.3/10. Published 2021-11-15.
How severe is CVE-2021-41263?
High severity. CVSS v3 base score is 8.3 out of 10.